Publications of the EOL team:

 
1. Cursive writing with smooth pursuit eye movements

Lorenceau J. Curr Biol; 2012 Aug 21;22(16):1506-9

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Abstract : The eyes never cease to move: ballistic saccades quickly turn the gaze toward peripheral targets, whereas smooth pursuit maintains moving targets on the fovea where visual acuity is best. Despite the oculomotor system being endowed with exquisite motor abilities, any attempt to generate smooth eye movements against a static background results in saccadic eye movements. Although exceptions to this rule have been reported, volitional control over smooth eye movements is at best rudimentary. Here, I introduce a novel, temporally modulated visual display, which, although static, sustains smooth eye movements in arbitrary directions. After brief training, participants gain volitional control over smooth pursuit eye movements and can generate digits, letters, words, or drawings at will. For persons deprived of limb movement, this offers a fast, creative, and personal means of linguistic and emotional expression. Copyright © 2012 Elsevier Ltd. All rights reserved.

 
2. A Bayesian computational model for online character recognition and disability assessment during cursive eye writing

Diard J, Rynik V and Lorenceau J (2013). Front. Psychol.4:843

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Abstract : This research involves a novel apparatus, in which the user is presented with an illusion inducing visual stimulus. The user perceives illusory movement that can be followed by the eye, so that smooth pursuit eye movements can be sustained in arbitrary directions. Thus, free-flow trajectories of any shape can be traced. In other words, coupled with an eye-tracking device, this apparatus enables "eye writing", which appears to be an original object of study. We adapt a previous model of reading and writing to this context. We describe a probabilistic model called the Bayesian Action-Perception for Eye On-Line model (BAP-EOL). It encodes probabilistic knowledge about isolated letter trajectories, their size, high-frequency components of the produced trajectory, and pupil diameter. We show how Bayesian inference, in this single model, can be used to solve several tasks, like letter recognition and novelty detection (i.e., recognizing when a presented character is not part of the learned database). We are interested in the potential use of the eye writing apparatus by motor impaired patients: the final task we solve by Bayesian inference is disability assessment (i.e., measuring and tracking the evolution of motor characteristics of produced trajectories). Preliminary experimental results are presented, which illustrate the method, showing the feasibility of character recognition in the context of eye writing. We then show experimentally how a model of the unknown character can be used to detect trajectories that are likely to be new symbols, and how disability assessment can be performed by opportunistically observing characteristics of fine motor control, as letter are being traced. Experimental analyses also help identify specificities of eye writing, as compared to handwriting, and the resulting technical challenges.

Reference Publications:

 
1. Automated classification and scoring of smooth pursuit eye movements
in the presence of fixations and saccades.

Komogortsev OV, Karpov A. Behav Res Methods; 2013 Mar;45(1):203-15

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Abstract : Ternary eye movement classification, which separates fixations, saccades, and smooth pursuit from the raw eye positional data, is extremely challenging. This article develops new and modifies existing eye-tracking algorithms for the purpose of conducting meaningful ternary classification. To this end, a set of qualitative and quantitative behavior scores is introduced to facilitate the assessment of classification performance and to provide means for automated threshold selection. Experimental evaluation of the proposed methods is conducted using eye movement records obtained from 11 subjects at 1000 Hz in response to a step-ramp stimulus eliciting fixations, saccades, and smooth pursuits. Results indicate that a simple hybrid method that incorporates velocity and dispersion thresholding allows producing robust classification performance. It is concluded that behavior scores are able to aid automated threshold selection for the algorithms capable of successful classification. voir

2. Contrast dependence of smooth pursuit eye movements following
a saccade to superimposed targets.

Fallah M, Reynolds JH. PLoS One; 2012;7(5):e37888

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Abstract : Dorsal stream areas provide motion information used by the oculomotor system to generate pursuit eye movements. Neurons in these areas saturate at low levels of luminance contrast. We therefore hypothesized that during the early phase of pursuit, eye velocity would exhibit an oculomotor gain function that saturates at low luminance contrast. To test this, we recorded eye movements in two macaques trained to saccade to an aperture in which a pattern of dots moved left or right. Shortly after the end of the saccade, the eyes followed the direction of motion with an oculomotor gain that increased with contrast before saturating. The addition of a second pattern of dots, moving in the opposite direction and superimposed on the first, resulted in a rightward shift of the contrast-dependent oculomotor gain function. The magnitude of this shift increased with the contrast of the second pattern of dots. Motion was nulled when the two patterns were equal in contrast. Next, we varied contrast over time. Contrast differences that disappeared before saccade onset biased post-saccadic eye movements at short latency. Changes in contrast occurring during or after saccade termination did not influence eye movements for approximately 150 ms. Earlier studies found that eye movements can be explained by a vector average computation when both targets are equal in contrast. We suggest that this averaging computation may reflect a special case of divisive normalization, yielding saturating contrast response functions that shift to the right with opposed motion, averaging motions when targets are equated in contrast.

3. Diversity of Neural Responses in the Brainstem during Smooth Pursuit Eye Movements Constrains the Circuit Mechanisms of Neural Integration.

Joshua M, Medina JF, Lisberger SG ; J Neurosci; 2013 Apr 10;33(15):6633-47

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Abstract : Neural integration converts transient events into sustained neural activity. In the smooth pursuit eye movement system, neural integration is required to convert cerebellar output into the sustained discharge of extraocular motoneurons. We recorded the expression of integration in the time-varying firing rates of cerebellar and brainstem neurons in the monkey during pursuit of step-ramp target motion. Electrical stimulation with single shocks in the cerebellum identified brainstem neurons that are monosynaptic targets of inhibition from the cerebellar floccular complex. They discharge in relation to eye acceleration, eye velocity, and eye position, with a stronger acceleration signal than found in most other brainstem neurons. The acceleration and velocity signals can be accounted for by opponent contributions from the two sides of the cerebellum, without integration; the position signal implies participation in the integrator. Other neurons in the vestibular nucleus show a wide range of blends of signals related to eye velocity and eye position, reflecting different stages of integration. Neurons in the abducens nucleus discharge homogeneously in relation mainly to eye position, and reflect almost perfect integration of the cerebellar outputs. Average responses of neural populations and the diverse individual responses of large samples of individual neurons are reproduced by a hierarchical neural circuit based on a model suggested the anatomy and physiology of the larval zebrafish brainstem. The model uses a combination of feedforward and feedback connections to support a neural circuit basis for integration in monkeys and other species.

4. Cognitive processes involved in smooth pursuit eye movements: behavioral evidence, neural substrate and clinical correlation.

Fukushima K, Fukushima J, Warabi T, Barnes GR ; Front Syst Neurosci; 2013;7:4.

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Abstract : Smooth-pursuit eye movements allow primates to track moving objects. Efficient pursuit requires appropriate target selection and predictive compensation for inherent processing delays. Prediction depends on expectation of future object motion, storage of motion information and use of extra-retinal mechanisms in addition to visual feedback. We present behavioral evidence of how cognitive processes are involved in predictive pursuit in normal humans and then describe neuronal responses in monkeys and behavioral responses in patients using a new technique to test these cognitive controls. The new technique examines the neural substrate of working memory and movement preparation for predictive pursuit by using a memory-based task in macaque monkeys trained to pursue (go) or not pursue (no-go) according to a go/no-go cue, in a direction based on memory of a previously presented visual motion display. Single-unit task-related neuronal activity was examined in medial superior temporal cortex (MST), supplementary eye fields (SEF), caudal frontal eye fields (FEF), cerebellar dorsal vermis lobules VI-VII, caudal fastigial nuclei (cFN), and floccular region. Neuronal activity reflecting working memory of visual motion direction and go/no-go selection was found predominantly in SEF, cerebellar dorsal vermis and cFN, whereas movement preparation related signals were found predominantly in caudal FEF and the same cerebellar areas. Chemical inactivation produced effects consistent with differences in signals represented in each area. When applied to patients with Parkinson's disease (PD), the task revealed deficits in movement preparation but not working memory. In contrast, patients with frontal cortical or cerebellar dysfunction had high error rates, suggesting impaired working memory. We show how neuronal activity may be explained by models of retinal and extra-retinal interaction in target selection and predictive control and thus aid understanding of underlying pathophysiology.

5. Cortical oscillatory changes in human middle temporal cortex underlying smooth pursuit eye movements.

Dunkley BT, Freeman TC, Muthukumaraswamy SD, Singh KD. ; Hum Brain Mapp; 2013 Apr;34(4):837-51.

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Abstract : Extra-striate regions are thought to receive non-retinal signals from the pursuit system to maintain perceptual stability during eye movements. Here, we used magnetoencephalography (MEG) to study changes in oscillatory power related to smooth pursuit in extra-striate visual areas under three conditions: 'pursuit' of a small target, 'retinal motion' of a large background and 'pursuit + retinal motion' combined. All stimuli moved sinusoidally. MEG source reconstruction was performed using synthetic aperture magnetometry. Broadband alpha-beta suppression (5-25 Hz) was observed over bilateral extra-striate cortex (consistent with middle temporal cortex (MT+)) during all conditions. A functional magnetic resonance imaging study using the same experimental protocols confirmed an MT+ localisation of this extra-striate response. The alpha-beta envelope power in the 'pursuit' condition showed a hemifield-dependent eye-position signal, such that the global minimum in the alpha-beta suppression recorded in extra-striate cortex was greatest when the eyes were at maximum contralateral eccentricity. The 'retinal motion' condition produced sustained alpha-beta power decreases for the duration of stimulus motion, while the 'pursuit + retinal motion' condition revealed a double-dip 'W' shaped alpha-beta envelope profile with the peak suppression contiguous with eye position when at opposing maximum eccentricity. These results suggest that MT+ receives retinal as well as extra-retinal signals from the pursuit system as part of the process that enables the visual system to compensate for retinal motion during eye movement. We speculate that the suppression of the alpha-beta rhythm reflects either the integration of an eye position-dependent signal or one that lags the peak velocity of the sinusoidally moving target. Copyright © 2011 Wiley Periodicals, Inc

6. Predictive saccade in the absence of smooth pursuit: interception of moving targets in the archer fish.

Ben-Simon A, Ben-Shahar O, Vasserman G, Segev R. ; J Exp Biol; 2012 Dec 15;215(Pt 24):4248-54.

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Abstract : Interception of fast-moving targets is a demanding task many animals solve. To handle it successfully, mammals employ both saccadic and smooth pursuit eye movements in order to confine the target to their area centralis. But how can non-mammalian vertebrates, which lack smooth pursuit, intercept moving targets? We studied this question by exploring eye movement strategies employed by archer fish, an animal that possesses an area centralis, lacks smooth pursuit eye movements, but can intercept moving targets by shooting jets of water at them. We tracked the gaze direction of fish during interception of moving targets and found that they employ saccadic eye movements based on prediction of target position when it is hit. The fish fixates on the target's initial position for 0.2 s from the onset of its motion, a time period used to predict whether a shot can be made before the projection of the target exits the area centralis. If the prediction indicates otherwise, the fish performs a saccade that overshoots the center of gaze beyond the present target projection on the retina, such that after the saccade the moving target remains inside the area centralis long enough to prepare and perform a shot. These results add to the growing body of knowledge on biological target tracking and may shed light on the mechanism underlying this behavior in other animals with no neural system for the generation of smooth pursuit eye movements.

7. Smooth pursuit and visual occlusion: active inference and oculomotor control in schizophrenia.

Adams RA, Perrinet LU, Friston K. ;PLoS One; 2012;7(10):e47502.

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Abstract : This paper introduces a model of oculomotor control during the smooth pursuit of occluded visual targets. This model is based upon active inference, in which subjects try to minimise their (proprioceptive) prediction error based upon posterior beliefs about the hidden causes of their (exteroceptive) sensory input. Our model appeals to a single principle – the minimisation of variational free energy – to provide Bayes optimal solutions to the smooth pursuit problem. However, it tries to accommodate the cardinal features of smooth pursuit of partially occluded targets that have been observed empirically in normal subjects and schizophrenia. Specifically, we account for the ability of normal subjects to anticipate periodic target trajectories and emit pre-emptive smooth pursuit eye movements – prior to the emergence of a target from behind an occluder. Furthermore, we show that a single deficit in the postsynaptic gain of prediction error units (encoding the precision of posterior beliefs) can account for several features of smooth pursuit in schizophrenia: namely, a reduction in motor gain and anticipatory eye movements during visual occlusion, a paradoxical improvement in tracking unpredicted deviations from target trajectories and a failure to recognise and exploit regularities in the periodic motion of visual targets. This model will form the basis of subsequent (dynamic causal) models of empirical eye tracking measurements, which we hope to validate, using psychopharmacology and studies of schizophrenia.

8. Shared attention for smooth pursuit and saccades.

Jin Z, Reeves A, Watamaniuk SN, Heinen SJ. ; J Vis; 2013;13(4).

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Abstract : Identification of brief luminance decrements on parafoveal stimuli presented during smooth pursuit improves when a spot pursuit target is surrounded by a larger random dot cinematogram (RDC) that moves with it (Heinen, Jin, & Watamaniuk, 2011). This was hypothesized to occur because the RDC provided an alternative, less attention-demanding pursuit drive, and therefore released attentional resources for visual perception tasks that are shared with those used to pursue the spot. Here, we used the RDC as a tool to probe whether spot pursuit also shares attentional resources with the saccadic system. To this end, we set out to determine if the RDC could release attention from pursuit of the spot to perform a saccade task. Observers made a saccade to one of four parafoveal targets that moved with the spot pursuit stimulus. The targets either moved alone or were surrounded by an RDC (100% coherence). Saccade latency decreased with the RDC, suggesting that the RDC released attention needed to pursue the spot, which was then used for the saccade task. Additional evidence that attention was released by the RDC was obtained in an experiment in which attention was anchored to the fovea by requiring observers to detect a brief color change applied 130 ms before the saccade target appeared. This manipulation eliminated the RDC advantage. The results imply that attentional resources used by the pursuit and saccadic eye movement control systems are shared.

9. Cerebellum and eye movement control -- neuronal mechanisms of memory-based smooth-pursuit and their early clinical application.

Fukushima K, Fukushima J, Ito N, Takei H, Ikeno K, Olley PM, Chiba S, Kobayashi N, Inoue K, Warabi T.Rinsho Shinkeigaku; 2012;52(11):1001-5.

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Abstract : Recent studies implicate the cerebellum in cognitive functions in addition to its well-established roles in motor control and learning. Using a memory-based smooth-pursuit task that separates visual working memory from motor preparation and execution, monkeys were trained to pursue (i.e., go) or not pursue (i.e., no-go), a cued direction, based on the working memory of visual motion-direction and a go/no-go instruction. Task-related neuronal activity was examined in cerebral and cerebellar major smooth-pursuit pathways. Different cerebral and cerebellar areas carried distinctly different signals during memory-based smooth-pursuit. In the cerebellum, prediction-related signals (visual working memory, pursuit selection and movement preparation) were represented in the vermal lobules VI-VII and caudal fastigial nucleus, whereas the floccular region (flocculus and ventral paraflocculus) contained predominantly execution-related signals. This task was applied to patients with cerebellar degeneration and idiopathic Parkinson's disease (PD). None of the PD patients tested exhibited impaired working memory of motion-direction and/or go/no-go selection, but they did show task-specific difficulty in generating an initial smooth-pursuit component, suggesting difficulty in smooth-pursuit preparation. In contrast, most cerebellar patients exhibited impaired visual working memory in addition to difficulty in preparing for and executing smooth-pursuit. These results suggest different roles for the basal ganglia and cerebellum in smooth-pursuit planning.

10. Subthalamic deep brain stimulation improves smooth pursuit and saccade performance in patients with Parkinson's disease.

Nilsson MH, Patel M, Rehncrona S, Magnusson M, Fransson PA. J Neuroeng Rehabil; 2013;10:33.

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Abstract : BACKGROUND: Deep brain stimulation (DBS) in the subthalamic nucleus (STN) significantly reduces symptoms of Parkinson's disease (PD) such as bradykinesia, tremor and rigidity. It also reduces the need for anti-PD medication, and thereby potential side-effects of L-Dopa. Although DBS in the STN is a highly effective therapeutic intervention in PD, its mechanism and effects on oculomotor eye movement control and particularly smooth pursuit eye movements have to date rarely been investigated. Furthermore, previous reports provide conflicting information. The aim was to investigate how DBS in STN affected oculomotor performance in persons with PD using novel analysis techniques. METHODS: Twenty-five patients were eligible (22 males, 3 females) according to the clinical inclusion criteria: idiopathic PD responsive to L-Dopa and having had bilateral STN stimulation for at least one year to ensure stable DBS treatment. Fifteen patients were excluded due to the strict inclusion criteria applied to avoid interacting and confounding factors when determining the effects of DBS applied alone without PD medication. One patient declined participation. Nine PD patients (median age 63, range 59-69 years) were assessed after having their PD medications withdrawn overnight. They were examined with DBS ON and OFF, with the ON/OFF order individually randomized. RESULTS: DBS ON increased smooth pursuit velocity accuracy (p < 0.001) and smooth pursuit gain (p = 0.005), especially for faster smooth pursuits (p = 0.034). DBS ON generally increased saccade amplitude accuracy (p = 0.007) and tended to increase peak saccade velocity also (p = 0.087), specifically both saccade velocity and amplitude accuracy for the 20 and 40 degree saccades (p < 0.05). Smooth pursuit latency tended to be longer (p = 0.090) approaching normal with DBS ON. Saccade latency was unaffected. CONCLUSIONS: STN stimulation from DBS alone significantly improved both smooth pursuit and saccade performance in patients with PD. The STN stimulation enhancement found for oculomotor performance suggests clear positive implications for patients' ability to perform tasks that rely on visual motor control and visual feedback. The new oculomotor analysis methods provide a sensitive vehicle to detect subtle pathological modifications from PD and the functional enhancements produced by STN stimulation from DBS alone.

11. Decreased ratio of downward to horizontal smooth pursuit eye movement velocity in a patient with Chiari I malformation: application in early detection of vestibulocerebellar malfunction.

Kobayashi M, Sugiyama A. Intern Med; 2012;51(15):2025-9.

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Abstract : A 72-year-old man presented with dizziness and left hand muscle atrophy. Magnetic resonance imaging revealed a spinal cord cavity and descent of the cerebellar tonsils. His diagnosis was Chiari I malformation with syringomyelia. No cerebellar signs were observed on physical examination. The cause of dizziness was investigated using a video-based eye movement tracker, which revealed a downward smooth pursuit velocity gain significantly below normal when expressed relative to the horizontal pursuit velocity gain. Vestibulocerebellar damage can cause mild downward pursuit deficit. The downward to horizontal smooth pursuit velocity gain ratio may be a more sensitive means of detecting vestibulocerebellar damage early.

12. Eye movement impairments in Parkinson's disease: possible role of extradopaminergic mechanisms.

Pinkhardt EH, Jürgens R, Lulé D, Heimrath J, Ludolph AC, Becker W, Kassubek J. BMC Neurol; 2012;12:5.

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Abstract : BACKGROUND: The basal ganglia (BG) are thought to play an important role in the control of eye movements. Accordingly, the broad variety of subtle oculomotor alterations that has been described in Parkinson's disease (PD) are generally attributed to the dysfunction of the BG dopaminergic system. However, the present study suggest that dopamine substitution is much less effective in improving oculomotor performance than it is in restoring skeletomotor abilities. METHODS: We investigated reactive, visually guided saccades (RS), smooth pursuit eye movements (SPEM), and rapidly left-right alternating voluntary gaze shifts (AVGS) by video-oculography in 34 PD patients receiving oral dopaminergic medication (PD-DA), 14 patients with deep brain stimulation of the nucleus subthalamicus (DBS-STN), and 23 control subjects (CTL);In addition, we performed a thorough review of recent literature according therapeuthic effects on oculomotor performance in PD by switching deep brain stimulation off and on in the PD-DBS patients, we achieved swift changes between their therapeutic states without the delays of dopamine withdrawal. In addition, participants underwent neuropsychological testing. RESULTS: Patients exhibited the well known deficits such as increased saccade latency, reduced SPEM gain, and reduced frequency and amplitude of AVGS. Across patients none of the investigated oculomotor parameters correlated with UPDRS III whereas there was a negative correlation between SPEM gain and susceptibility to interference (Stroop score). Of the observed deficiencies, DBS-STN slightly improved AVGS frequency but neither AVGS amplitude nor SPEM or RS performance. CONCLUSIONS: We conclude that the impairment of SPEM in PD results from a cortical, conceivably non-dopaminergic dysfunction, whereas patients' difficulty to rapidly execute AVGS might be related to their BG dysfunction.

13. A vermal Purkinje cell simple spike population response encodes the changes in eye movement kinematics due to smooth pursuit adaptation.

Dash S, Dicke PW, Thier P.Front Syst Neurosci; 2013;7:3.

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Abstract : Smooth pursuit adaptation (SPA) is an example of cerebellum-dependent motor learning that depends on the integrity of the oculomotor vermis (OMV). In an attempt to unveil the neuronal basis of the role of the OMV in SPA, we recorded Purkinje cell simple spikes (PC SS) of trained monkeys. Individual PC SS exhibited specific changes of their discharge patterns during the course of SPA. However, these individual changes did not provide a reliable explanation of the behavioral changes. On the other hand, the population response of PC SS perfectly reflected the changes resulting from adaptation. Population vector was calculated using all cells recorded independent of their location. A population code conveying the behavioral changes is in full accordance with the anatomical convergence of PC axons on target neurons in the cerebellar nuclei. Its computational advantage is the ease with which it can be adjusted to the needs of the behavior by changing the contribution of individual PC SS based on error feedback.

14. Who doesn't benefit from psychosomatic rehabilitation?

Lange M, Franke W, Petermann F.Rehabilitation (Stuttg); 2012 Dec;51(6):392-7.

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Abstract : BACKGROUND: The aim of this study was to examine how far treatment success in psychosomatic rehabilitation can be predicted by patients' characteristics, therapy motivation and disorder. METHODS: Data of 307 patients with psychosomatic disease were included. External and self-evaluations were operationalized as criterion for success. Data were collected using the Brief Symptom Inventory (BSI), Patients' Questionnaire of Therapy Motivation (PAREMO-20) and Disorder Severity Score (BSS). Hierarchical linear regression analysis was used for data analysis. RESULTS AND CONCLUSIONS: A sceptical attitude, low education and long time of incapacity for work prior to rehabilitation can predict a lower treatment success. High levels of readiness for change and 6-8 working hours daily seem to favourably impact coping with disease in the framework of inpatient psychosomatic rehabilitation. © Georg Thieme Verlag KG Stuttgart · New York.

15. Early surgical rehabilitation due to modified exenteration technique.

Wirth-Welle RB, Chaloupka K. Klin Monbl Augenheilkd; 2013 Apr;230(4):380-4.

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Abstract : BACKGROUND: Orbital exenteration is a life intruding surgical procedure with severe functional, aesthetic and psychological consequences. Apart from the correct tumor treatment, early aesthetic and psychosocial rehabilitation is crucial for the well-being of the patient. We discuss reasons leading to exenteration and present new surgical techniques. Local flaps in the anterior socket improve wound healing allowing early placement of the prosthesis and therefore faster social rehabilitation of the patient. PATIENTS AND METHODS: Between 2007 and 2011 seven patients with malignant orbital tumors (1 × plasmocytoma, 1 × melanoma, 1 × sarcoma, 1 × squamous cell carcinoma and 3 × basal cell carcinoma) received a radical orbital exenteration at the Department of Ophthalmology of the Zurich University Hospital. The medical histories were evaluated according to reasons for exenteration, surgical techniques and postoperative follow-up. Reconstruction of the anterior socket border succeeded using local flaps (Mustardé, Glabella and combined with further modified pedicled local full thickness skin flaps). The central defects were covered with split skin graft from the thigh. RESULTS: Three weeks after surgery the anterior border of the socket was completely healed without problems by local flaps with good blood supply. This allowed the early prosthetic fitting and wearing as well as quick social rehabilitation of the patient. CONCLUSIONS: The use of local flaps improves wound healing even in anticoagulated patients. This reduces the time of hospitalization and rehabilitation, and allows an early, satisfactory, social reintegration of the patient. Georg Thieme Verlag KG Stuttgart · New York.

16. Symptom validity in psychosomatic rehabilitation.

Kobelt A, Göbber J, Bassler M, Petermann F.Rehabilitation (Stuttg); 2012 Oct;51(5):349-55.

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Abstract : OBJECTIVES: This study investigates how patients in psychosomatic rehabilitation are characterized, who show conspicuous response behavior in a symptom validation test. At the same time the question of whether patients with an unlikely response behavior may benefit from psychosomatic rehabilitation will be pursued. RESEARCH QUESTION: What proportion of patients in an inpatient psychosomatic rehabilitation clinic shows results in their symptom validation test that lack clear interpretability due to unlikely complaint representation? How can this group of patients be characterized? How effective is the psychosomatic rehabilitation treatment in patients who stand out by an unlikely response style? METHODS: Patients completed a questionnaire at the beginning and the end of their inpatient psychosomatic rehabilitation treatment. Questionnaire included socio-demographic information, Health49, SPE, DIAMO, FBTM and SIMS. Additionally, data from the discharge letter were considered. RESULTS: 24.6% of 329 patients showed conspicuous response behavior. Patients with conspicuous complaint representation were more likely to have an immigration background, rather belonged to the socio-economic underclass and more frequently showed a vulnerable gainful employment. There was no correlation between SIMS and the rehabilitation outcome. Patients with conspicuous response behavior and with high depression scores benefited significantly less from the inpatient treatment. Differences in the ability to work assessment were not found. CONCLUSION: Conspicuous response style is associated with high scores on the clinical symptom scales. About one quarter of patients in an inpatient psychosomatic rehabilitation clinic needs a more accurate diagnosis in order to reliably assess the clinical prognosis and the ability to work. © Georg Thieme Verlag KG Stuttgart · New York.

17. Smooth-pursuit changes after the tenotomy and reattachment procedure for infantile nystagmus syndrome: model predictions and patient data.

Wang ZI, Dell'Osso LF, Prakash S, Chen X. J Pediatr Ophthalmol Strabismus; 2012 Sep-Oct;49(5):295-302.

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Abstract : PURPOSE: Patients with infantile nystagmus syndrome (INS) often cannot quickly locate new visual targets or track moving objects. Dynamic demands on visual function are not measured by static measures (eg, visual acuity); they require time-sensitive measures. The authors investigated how dynamic properties of INS (pursuit-target acquisition times) were affected by the tenotomy and reattachment (T&R) procedure in both patients with INS and behavioral ocular motor system model predictions. METHODS: Responses of 3 patients with different INS waveforms were compared before and after T&R to test the model's predictions. A high-speed digital video system was used to take eye-movement data. Human responses to target-ramp stimuli were analyzed. RESULTS: T&R did not improve the smooth-pursuit responses of patients with INS; pursuit-target acquisition times did not show marked improvements. However, in one case, T&R allowed the patient to pursue targets "faster" in a specific direction. CONCLUSION: T&R can improve peak visual acuity, broaden the high-acuity gaze-angle range, and reduce target acquisition times to static targets but not moving targets. When the target moves simultaneously with an ongoing saccade in the nystagmus cycle, the steady-state errors and elongated target acquisition times observed might be part of the intrinsic characteristics of normal pursuit responses. Copyright 2012, SLACK Incorporated.

18. Gaze control and vestibular-cervical-ocular responses after prolonged exposure to microgravity.

Kornilova LN, Naumov IA, Azarov KA, Sagalovitch VN. Aviat Space Environ Med; 2012 Dec;83(12):1123-34.

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Abstract : BACKGROUND: Microgravity does not affect visual function directly. However, because of the altered afferentation from vestibular, support, and tactile-proprioceptive systems, it could lead to disturbances in visual tracking and inhibit the cosmonaut's activity. Therefore, it is necessary to obtain quantitative evaluations of spaceflight effects upon gaze control and vestibular-cervical-ocular responses. METHODS: Examination of visual tracking with the head in a fixed position was performed in 26 Russian ISS cosmonauts before and after a prolonged spaceflight (129-215 d). As vestibular tests, we used several roll-tilts and yaw head rotations. Eye movements were recorded using both video-oculographic and electro-oculographic methods. RESULTS: It was shown that until 9 d after landing (R+9) spontaneous eye movements were increased (spontaneous nystagmus, gaze nystagmus, square wave jerks); otolith function was suppressed (inversion, absence, or significant decrease of the compensatory torsional ocular counter-rolling); vestibular reactivity was elevated (an increased intensity of the vestibular nystagmus during head yaw rotations); amplitude and velocity characteristics of gaze control (saccades, smooth pursuit, gaze holding) were significantly decreased; total reaction time was significantly increased up to 2-3 times; and gaze holding ability was degraded. For several cosmonauts, smooth pursuit was collapsed and their gaze approached the stimulus or pursued its motion utilizing a sequence of saccades at least until R+5. DISCUSSION: Prolonged exposure to microgravity considerably affects all forms of visual tracking. Revealed disturbances in precision of visual tracking and adoption of the new tracking strategy substantially prolong (up to 2-3 times) the period required to acquire, recognize, and to fixate gaze on the target.

19. Patient goals for medical rehabilitation - overview of the current state of research in Germany.

Buchholz I, Kohlmann T. Rehabilitation (Stuttg); 2013 Apr;52(2):75-85.

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Abstract : GOALS: It is widely known that goals and goal agreement are important components of a modern approach to medical rehabilitation. The present work gives an overview of the current state of research regarding patient goals for medical rehabilitation by reviewing relevant German pub-lications between 2000 and 2010. This review focused on (1) data collection methods of rehabilitation goals, (2) patient goals, and (3) agreement between the goals of patients and their clinicians. METHODS: A search strategy combining electronic databases and hand search was applied. A priori inclusion and exclusion criteria were applied. A self-developed goal-catalogue was used to synthesize the literature. RESULTS: A total of 20 publications were included, 11 of which explored both patient and clinicians perspectives. ad (1): Only 4 goal-assessment instruments in the field of medical rehabilitation exist, but none has been established as a standard. The instruments differ in how differentiate they depict different goals areas. ad (2): The goal structure of medical rehabilitation patients corresponds to the respective indications. The 3 top goals in all patient groups included physical and/or psychosocial objectives. Information and occupational goals are rarely represented among the 3 top goals mentioned. ad (3): Patients have more numerous as well as differing goals then their treating clinicians. Goals of physical functions (e. g., enhancement of stamina) and superior rehabilitation goals (e. g., return to work) have the best agreement. Mental and maintenance goals are more frequently mentioned by the patients while pain and symptom-related goals are more frequently mentioned by the doctors. There are indication-specific differences for goals regarding information. CONCLUSION: Rehabilitation goals are highly valuable in the rehabilitation process. Finding only 20 relevant publications, generalizability of study results is limited. Due to high variability in methodological approach and presentation of results, comparisons of results across studies reviewed are severely limited. Developing survey standards and using uniform metrics could contribute to standardizing study endpoints. The goals of patients and clinicians are formed in individual life or work contexts, which are influenced by numerous factors (e. g., knowledge, illness/health concepts, assumptions regarding rehabilitation treatment), representing individual expertise that complement one another. Since compatible goals are essential for successful rehabilitation treatment, an exchange of goals and expectations as well as the establishment of joint target agreements should precede any rehabilitation programme. © Georg Thieme Verlag KG Stuttgart · New York.