EyeSeeCam

The purpose of this study was to evaluate whether it is possible to restore the high-frequency angular vestibulo-ocular reflex (aVOR) in patients suffering from a severe bilateral vestibulopathy (BV) and implanted with a vestibular implant prototype. Three patients (S1-3) participated in the study. They received a prototype vestibular implant with one to three electrode branches implanted in the proximity of the ampullary branches of the vestibular nerve. Five electrodes were available for electrical stimulation: one implanted in proximity of the left posterior ampullary nerve in S1, one in the left lateral and another one in the superior ampullary nerves in S2, and one in the right lateral and another one in the superior ampullary nerves in S3...

Objective: There is increasing evidence that the cerebellum has a role in pain processing. The present study investigates whether chronic pain patients, who are likely to have altered pain processing, exhibit signs of subtle cerebellar dysfunction. We used oculomotor tasks to assess dysfunction of the associated neuronal networks, including the cerebellum. Methods: Thirty patients with chronic nonspecific spinal pain and 30 age- and sex-matched controls were enrolled...

BACKGROUND: Different analysis techniques are used to define vestibulo-ocular reflex (VOR) gain between eye and head angular velocity during the video head impulse test (vHIT). Comparisons would aid selection of gain techniques best related to head impulse characteristics and promote standardisation. OBJECTIVE: Compare and contrast known methods of calculating vHIT VOR gain. METHODS: We examined lateral canal vHIT responses recorded from 20 patients twice within 13 weeks of acute unilateral peripheral vestibular deficit onset...

INTRODUCTION: Earlier work revealed that vHIT examination is often difficult to perform on very young children. In particular, the calibration of the system can be difficult, as active cooperation of the patient is required. Additionally, the patient must be able to follow the examiner's instructions, which is challenging for very young children. Therefore, the aim of the present study was to develop and validate a new, software-based approach enabling vHIT testing of young children and infants...

BACKGROUND: Numerous video head impulse test (vHIT) devices are available commercially; however, gain is not calculated uniformly. An evaluation of these devices/algorithms in healthy controls and patients with vestibular loss is necessary for comparing and synthesizing work that utilizes different devices and gain calculations. PURPOSE: Using three commercially available vHIT devices/algorithms, the purpose of the present study was to compare: (1) horizontal canal vHIT gain among devices/algorithms in normal control subjects; (2) the effects of age on vHIT gain for each device/algorithm in normal control subjects; and (3) the clinical performance of horizontal canal vHIT gain between devices/algorithms for differentiating normal versus abnormal vestibular function...

OBJECTIVES: The aim of this study was to quantitatively measure the tightness of the goggle strap during the video head impulse test (vHIT) and to identify slippage-induced artifacts according to tightness. We aimed to elucidate the mechanism of faulty gain caused by goggle slippage and explain the typical artifacts associated with it. SUBJECTS AND METHODS: An endotracheal tube cuff manometer was coupled to the EyeSeeCam vHIT system (Interacoustics, Assens, Denmark) to monitor strap tightness...

We hypothesize that binocular coordination of saccades is based on continuous neuroplasticity involving interactions of saccades and vergence. To test this hypothesis we study reading saccades in young students who were diagnosed for vergence disorders before and after vergence rehabilitation. Following orthoptic evaluation and symptomatology screening, 5 weekly sessions of vergence rehabilitation were applied with the REMOBI vergence double step protocole (see Kapoula et al., 2016). Using the Eyeseecam videoculography device we measured vergence as well as saccades and fixations during a reading test four times: at the beginning and at the end of the first and of the fifth vergence rehabilitation session...

UNLABELLED: The vHIT (video head impulse test) investigates the vestibular function in two ways: a VOR (vestibulo-ocular reflex) gain value and a head impulse diagram. From the diagram covert and overt saccades can be detected. Evaluation of the vestibular function based on vHIT depends on both parameters. There is a lack of knowledge regarding the reliability of the two parameters. The objective was to investigate the reliability of vHIT by comparing gain values between examiners on the same subjects, and to see how differences affected the occurrence of saccades...

BACKGROUND: People with color vision deficiencies report numerous limitations in daily life, restricting, for example, their access to some professions. However, they use basic color terms systematically and in a similar manner as people with normal color vision. We hypothesize that a possible explanation for this discrepancy between color perception and behavioral consequences might be found in the gaze behavior of people with color vision deficiency. METHODS: A group of participants with color vision deficiencies and a control group performed several search tasks in a naturalistic setting on a lawn...

BACKGROUND: Patients with downbeat nystagmus syndrome suffer from oscillopsia, which leads to an unstable visual perception and therefore impaired visual acuity. The aim of this study was to use real-time computer-based visual feedback to compensate for the destabilizing slow phase eye movements. METHODS: The patients were sitting in front of a computer screen with the head fixed on a chin rest. The eye movements were recorded by an eye tracking system (EyeSeeCam®)...

BACKGROUND: A standardized diagnostic protocol for children's vestibular assessment is still missing in daily clinical life. As rotatory chair testing and caloric test are usually not tolerated well by children, the aim of our study was not only to evaluate the importance and practicability of the video head impulse test performed in children with and without balance problems, but also to outline a diagnostic algorithm for children with balance problems. METHODS: Fifty-five children aged 3-16 years have been included in this prospective monocentric study...

The effects of aging on eye movements are well studied in the laboratory. Increased saccade latencies or decreased smooth-pursuit gain are well established findings. The question remains whether these findings are influenced by the rather untypical environment of a laboratory; that is, whether or not they transfer to the real world. We measured 34 healthy participants between the age of 25 and 85 during two everyday tasks in the real world: (I) walking down a hallway with free gaze, (II) visual tracking of an earth-fixed object while walking straight-ahead...

Alterations of eye movements in schizophrenia patients have been widely described for laboratory settings. For example, gain during smooth tracking is reduced, and fixation patterns differ between patients and healthy controls. The question remains, whether such results are related to the specifics of the experimental environment, or whether they transfer to natural settings. Twenty ICD-10 diagnosed schizophrenia patients and 20 healthy age-matched controls participated in the study, each performing four different oculomotor tasks corresponding to natural everyday behavior in an indoor environment: (I) fixating stationary targets, (II) sitting in a hallway with free gaze, (III) walking down the hallway, and (IV) visually tracking a target on the floor while walking straight-ahead...

OBJECTIVE: To evaluate the validity of 2D video-oculography (VOG) compared with scleral search coils for horizontal AVOR gain estimation in older individuals. STUDY DESIGN: Cross-sectional validation study. SETTING: Tertiary care academic medical center. PATIENTS: Six individuals age 70 and older. INTERVENTIONS: Simultaneous eye movement recording with scleral search coil (over right eye) and EyeSeeCam VOG camera (over left eye) during horizontal head impulses...

Development of accurate Situation Awareness (SA) depends on experience and may be impaired during excessive workload. In order to gain adequate SA for decision making and performance, anaesthetists need to distribute visual attention effectively. Therefore, we hypothesized that in more experienced anaesthetists performance is better and increase of physiological workload is less during critical incidents. Additionally, we investigated the relation between physiological workload indicators and distribution of visual attention...

BACKGROUND: The decreased ability to carry out vertical saccades is a key symptom of Progressive Supranuclear Palsy (PSP). Objective measurement devices can help to reliably detect subtle eye movement disturbances to improve sensitivity and specificity of the clinical diagnosis. The present study aims at transferring findings from restricted stationary video-oculography (VOG) to a wearable head-mounted device, which can be readily applied in clinical practice. METHODS: We investigated the eye movements in 10 possible or probable PSP patients, 11 Parkinson's disease (PD) patients, and 10 age-matched healthy controls (HCs) using a mobile, gaze-driven video camera setup (EyeSeeCam)...

Patients suffering from homonymous hemianopia after infarction of the posterior cerebral artery (PCA) report different degrees of constraint in daily life, despite similar visual deficits. We assume this could be due to variable development of compensatory strategies such as altered visual scanning behavior. Scanning compensatory therapy (SCT) is studied as part of the visual training after infarction next to vision restoration therapy. SCT consists of learning to make larger eye movements into the blind field enlarging the visual field of search, which has been proven to be the most useful strategy(1), not only in natural search tasks but also in mastering daily life activities(2)...

Saccadic impairment in Alzheimer's disease (AD) was found in horizontal saccades. The present study extends investigation to vertical saccades in a large number of subjects, including AD and amnestic mild cognitive impairment (aMCI). We examined both horizontal and vertical saccades in 30 healthy elderly, 18 aMCI, and 25 AD. Two tasks were used: gap (fixation target extinguishes prior to target onset) and overlap (fixation stays on after target onset). Eye movements were recorded with the Eyeseecam system. (1) Robust gap effect (shorter latencies in gap than in overlap) exists for AD and aMCI patients as for healthy elderly; (2) abnormal long latency of saccades in gap and overlap tasks for AD relative to healthy elderly and aMCI patients; (3) longer latency for aMCI patients than for healthy elderly for the overlap task; (4) significant correlation between scores of Mini-Mental State Examination (MMSE) and latencies of saccades considering the AD group only; (5) higher coefficient of variation in latency for AD patients than for healthy elderly and for aMCI patients; (6) variability of accuracy and speed is abnormally higher in AD patients than in aMCI and healthy elderly...

Mobile eyetracking is a recent method enabling research on attention during real-life behavior. With the EyeSeeCam, we have recently presented a mobile eye-tracking device, whose camera-motion device (gazecam) records movies orientated in user's direction of gaze. Here we show that the EyeSeeCam can extract a reliable vergence signal, to measure the fixation distance. We extend the system to determine not only the direction of gaze for short distances more precisely, but also the fixation point in 3 dimensions (3D)...

BACKGROUND: Workload assessment is an important tool for improving patient safety in anaesthesia. We tested the hypothesis that heart rate, pupil size, and duration of fixation increase, whereas saccade amplitude decreases with increased workload during simulated critical incidents. METHODS: Fifteen trainee anaesthetists participated in this randomized cross-over trial. Each participant used a head-mounted eye-tracking device (EyeSeeCam) during induction of general anaesthesia in a full-scale simulation during three different sessions...