Ocular Motor Behavior Monitor in Intermittent Exotropia by Eye Tracker

Abstract Purpose: Eye movement in intermittent exotropia (IXT) patients is characterized by viability and uncertainty, however, conventional strabismus inspection methods cannot reflect these important qualities. Here, we sought to study the ocular motor behavior of IXT under different viewing conditions by eye tracker.Methods: Sixty-one IXT patients (33 males and 28 females) and 15 age-matched control participants were recruited for this study. An eye tracker equipped with a high-speed camera and MATLAB software was employed to monitor and record eye movement as well as eye position in included subjects with 3D shutter glasses at a normal reading distance (57 cm).Results: By using an eye tracker, our data showed that 90% of the included IXT patients lost their control and showed exotropia in 1.5±2.1s. The average deviation degree measured by the eye tracker was 32.9±11.5△, ranging from 6 to 50△, and reached its maximum deviation degree at 36.9±12.4△, with a mean time of 2±1.5s. Although a significant difference exists in the strabismus quantification between the prism test and the eye tracker, the test results obtained from these two methods were positively correlated. Moreover, by using the eye tracker, the fixation instability of IXT patients could be easily recorded and analyzed. In addition, the included IXT patients were divided into three types according to their ocular motor behavior as monitored by an eye tracker.Conclusion: Eye trackers could not only provide continuous, precise and effective strabismus assessments but also analyze ocular motor behavior over a period of time in IXT patients.

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Visual behavior and upper limb variability in coordination comparision between novices and experts performers in basketball free throws

Latin American Journal of Development ◽

10.46814/lajdv3n5-006 ◽

2021 ◽

Vol 3 (5) ◽

pp. 2832-2841

Author(s):

Alejandro Troncoso T ◽

Christian Cancino B ◽

Juan José Marimán ◽

Joel Álvarez-Ruf

Keyword(s):

Upper Limb ◽

High Speed ◽

Motor Behavior ◽

Time Windows ◽

Visual Fixation ◽

Visual Behavior ◽

Eye Tracker ◽

Expert Performance ◽

Significant Difference ◽

Expert And Novice

The objective of the present research is to determine the differences in visual behavior and the upper limbs variability in coordination between expert performers and novice performers in basketball free throws. Methods: Nine right-handed men were tested. The skilled group consisted of four players who had an experience of 9.2 years (SD: 1.2) and play 9 hours per week (SD: 12). The novice group consisted of five players with no experience in Basketball. Visual behavior was evaluated using an eye-tracker head mounted and the upper limb kinematic behavior using a High-speed camera during 30 free throws. Results: There was a significant difference between the expert and novice performers in accuracy for the 30 trials (p<0.034). In Visual behavior were no significant differences the duration of the last visual fixation before the onset of elbow extension in execution phase (p>0,05) between expert and novice groups. There were statistically significant differences in the elbow-wrist variability in coordination in the throws duration time-windows of 100%, 90%, 80%, 30% (pvalue <0.05). 100% represent the last time-windows before ball release. The expert performers shows greater consistency in coordination, however novice subjects exhibit greater variability in the coordination in these intervals. Conclusion: The results suggest that the task of shooting free throws requires a long visual fixation to the site of interest, which temporarily is similar in subjects with different levels of skill. The higher reproducibility pattern suggests elbow-wrist coordination to be the key perceptuo-motor behavior in order to reach expert performance. El objetivo de la presente investigación es determinar las diferencias en el comportamiento visual y la variabilidad de los miembros superiores en la coordinación entre ejecutantes expertos y ejecutantes novatos en los tiros libres de baloncesto. Métodos: Se examinaron nueve hombres diestros. El grupo de expertos estaba formado por cuatro jugadores que tenían una experiencia de 9,2 años (SD: 1,2) y jugaban 9 horas a la semana (SD: 12). El grupo de novatos estaba formado por cinco jugadores sin experiencia en baloncesto. El comportamiento visual fue evaluado utilizando un eye-tracker montado en la cabeza y el comportamiento cinemático del miembro superior utilizando una cámara de alta velocidad durante 30 tiros libres. Resultados: Hubo una diferencia significativa entre los expertos y los novatos en la precisión de los 30 ensayos (p<0,034). En el comportamiento visual no hubo diferencias significativas en la duración de la última fijación visual antes del inicio de la extensión del codo en la fase de ejecución (p>0,05) entre los grupos de expertos y novatos. Hubo diferencias estadísticamente significativas en la variabilidad codo-muñeca en la coordinación en las ventanas de tiempo de duración de los lanzamientos del 100%, 90%, 80%, 30% (pvalor <0,05). El 100% representa las últimas ventanas de tiempo antes del lanzamiento del balón. Los ejecutantes expertos muestran una mayor consistencia en la coordinación, sin embargo los sujetos novatos exhiben una mayor variabilidad en la coordinación en estos intervalos. Conclusiones: Los resultados sugieren que la tarea de lanzar tiros libres requiere una larga fijación visual al sitio de interés, que temporalmente es similar en sujetos con diferentes niveles de habilidad. El patrón de mayor reproducibilidad sugiere que la coordinación codo-muñeca es la conducta perceptivo-motora clave para alcanzar un rendimiento experto.

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The Influence of Articulatory Suppression on Reading Among Chinese Children with Developmental Dyslexia: An Eye-Movement and Case-Control Study

10.21203/rs.3.rs-45291/v1 ◽

2020 ◽

Author(s):

Xiuhong Li ◽

Weidong Li ◽

Buyun Liu ◽

Jinxin Zhang ◽

Jingwen Ma ◽

...

Keyword(s):

Eye Movement ◽

Developmental Dyslexia ◽

Reading Ability ◽

High Speed ◽

Articulatory Suppression ◽

Reading Speed ◽

Chinese Children ◽

Phonological Loop ◽

Eye Tracker ◽

Core Deficit

Abstract Background: In Western countries, phonological processing deficit was regard as a core deficit in developmental dyslexia (DD). As Chinese is a logographic language, it’s still controversial whether and how the articulatory suppression influences reading ability and processing of Chinese children with DD. The study aimed to examine how the phonological loop influences reading ability and processing in Chinese children with DD.Methods: This study included 30 children with DD and 37 children without DD. Two types of articles (i.e., scenery prose and narrative story) and two conditions (under the conditions of articulatory-suppression and silent reading) were applied. An eye-link II High-Speed Eye Tracker was used to track a series of eye-movement parameters. The data was analyzed by the linear Mixed-Effects model. Results: Compared with children without DD, Children with DD had lower reading achievement (RA), frequency of saccades (FS) and frequency of fixations (FF), longer reading time (RT) and average fixation duration (AFD), slower reading speed (RS), shorter average saccade amplitude (ASA) and fixation distance (FD), more number of fixations (NF) and number of saccades (NS). There were significant interactions between participant group and articulatory suppression on RT and FD. We also observed interaction effects between article types and articulatory suppression on RA, AFD, ASA, and FS.Conclusion: Children DD exhibit abnormal phonological loop and eye movements while reading. The role of the articulatory suppression on reading varies with the presentation of DD and the article type.

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The Influence of Articulatory Suppression on Reading Among Chinese Children With Developmental Dyslexia: An Eye-Movement Study

Frontiers in Pediatrics ◽

10.3389/fped.2021.758615 ◽

2021 ◽

Vol 9 ◽

Author(s):

Xiuhong Li ◽

Weidong Li ◽

Buyun Liu ◽

Jinxin Zhang ◽

Jingwen Ma ◽

...

Keyword(s):

Eye Movement ◽

Developmental Dyslexia ◽

Reading Ability ◽

High Speed ◽

Articulatory Suppression ◽

Reading Speed ◽

Chinese Children ◽

Phonological Loop ◽

Eye Tracker ◽

Movement Parameters

Objective: The study aimed to examine how the phonological loop influences reading ability and processing in Chinese children with developmental dyslexia (DD).Methods: This study included 30 children with DD and 37 children without DD. Two types of articles (i.e., scenery prose and narrative story) and two conditions (under the conditions of articulatory-suppression and silent reading) were applied. An eye-link II High-Speed Eye Tracker was used to track a series of eye-movement parameters. The data were analyzed by the linear Mixed-Effects model.Results: Compared with children without DD, Children with DD had lower reading achievement (RA), frequency of saccades (FS) and frequency of fixations (FF), longer reading time (RT) and average fixation duration (AFD), slower reading speed (RS), shorter average saccade amplitude (ASA) and fixation distance (FD), more number of fixations (NF), and number of saccades (NS). There were significant interactions between participant group and articulatory suppression on RT and FD. We also observed interaction effects between article types and articulatory suppression on RA, AFD, ASA, and FS.Conclusion: Children DD exhibit abnormal phonological loop and eye movements while reading. The role of articulatory suppression on reading varies with the presentation of DD and the article type.

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Efficacies of preoperative prism adaptation test and monocular occlusion for detecting the maximum angle of deviation in intermittent exotropia

10.21203/rs.3.rs-598170/v1 ◽

2021 ◽

Author(s):

Ryota Takada ◽

Fumiko Matsumoto ◽

Akemi Wakayama ◽

Takuya Numata ◽

Fumi Tanabe ◽

...

Keyword(s):

Strabismus Surgery ◽

Prism Adaptation ◽

Maximum Deviation ◽

Intermittent Exotropia ◽

Optimal Test ◽

Maximum Angle ◽

Significant Difference ◽

Adaptation Test ◽

Angle Of Deviation ◽

Distance Deviation

Abstract Purpose: The efficacies of prism adaptation test (PAT) and monocular occlusion (MO) and their optimal test durations to detect the maximum angles of deviation at near and distance in eyes with intermittent exotropia (IXT) were assessed and compared. Methods: We retrospectively reviewed the medical records of 72 patients with IXT, who had undergone the initial strabismus surgery between April 2015 and October 2018 and had been preoperatively tested by PAT and MO. The near and distance deviations measured after 30- and 60-minute PAT and MO were compared with the baseline measurements obtained immediately after prism wear and before occlusion. The measurements and the required durations for obtaining the maximum deviation angle were also compared between PAT and MO. Results: Compared with the baseline, the near deviation by PAT significantly increased after 30 (p < 0.05) and 60 (p < 0.01) minutes but not the distance deviation. Besides, the increase in the near deviation after 30 minutes was not significant. By MO, neither near nor distance deviation showed a significant difference from the baseline after 30 and 60 minutes. While the near deviations by PAT were significantly greater than those by MO at 30 and 60 minutes, a similar result was only observed at 30 minutes in the distance deviation. Conclusion: A 30-minute PAT appears to be more effective than MO in revealing the maximum angle of deviation before strabismus surgery.

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Eye-Tracker Analysis of the Contrast Sensitivity of Anomalous and Normal Trichromats: A Loglinear Examination with Landolt-C Figures

Applied Sciences ◽

10.3390/app11073200 ◽

2021 ◽

Vol 11 (7) ◽

pp. 3200

Author(s):

László Sipos ◽

Attila Gere ◽

Zoltán Kókai ◽

Ákos Nyitrai ◽

Sándor Kovács ◽

...

Keyword(s):

Survival Analysis ◽

Contrast Sensitivity ◽

Eye Movement ◽

Fixation Duration ◽

Tracking System ◽

Eye Tracker ◽

Significant Difference ◽

Visit Duration ◽

The Right ◽

Landolt C

The contrast sensitivity of normal and anomalous trichromats were examined with Landolt-C figures by eye-tracking system. For the measurements, two series of test images (achromatic and colored) were designed. The difficulty levels of the tests were gradually increased after each right answer. In the case of the observation of the ring of the Landolt-C figures, the variables related to fixation duration, fixation count, visit duration and count significantly affected this subject, success or image parameters, and their interactions. The main questions of this study were as follows: Which statistical method is suitable to model the differences between anomalous and normal trichromats? Which eye-movement variables have a significant effect on the investigated parameters and on their interactions? Is there any significant difference between eye-movement variables of normal and anomalous trichromats? How does the survival time of anomalous and normal trichromats change in the case of achromatic and colored figures? The results showed that the right answers of anomalous and normal trichromats can be described with multiple or cross-classified contingency tables evaluated effectively by loglinear regression. The survival analysis showed that normal trichromats are more successful in interpreting colored images, while anomalous trichromats seemed to be more efficient in perceiving achromatic images.

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Online Removal of Eye Movement and Blink EEG Artifacts Using a High-Speed Eye Tracker

IEEE Transactions on Biomedical Engineering ◽

10.1109/tbme.2011.2108295 ◽

2012 ◽

Vol 59 (8) ◽

pp. 2103-2110 ◽

Cited By ~ 45

Author(s):

B. Noureddin ◽

P. D. Lawrence ◽

G. E. Birch

Keyword(s):

Eye Movement ◽

High Speed ◽

Eye Tracker ◽

Eeg Artifacts

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Efficacies of preoperative prism adaptation test and monocular occlusion for detecting the maximum angle of deviation in intermittent exotropia

BMC Ophthalmology ◽

10.1186/s12886-021-02060-9 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Ryota Takada ◽

Fumiko Matsumoto ◽

Akemi Wakayama ◽

Takuya Numata ◽

Fumi Tanabe ◽

...

Keyword(s):

Strabismus Surgery ◽

Prism Adaptation ◽

Maximum Deviation ◽

Test Duration ◽

Intermittent Exotropia ◽

Maximum Angle ◽

Significant Difference ◽

Adaptation Test ◽

Angle Of Deviation ◽

Distance Deviation

Abstract Background The efficacies of prism adaptation test (PAT) and monocular occlusion (MO) and their optimal test durations to detect the maximum angles of deviation at near and distance in eyes with intermittent exotropia (IXT) were assessed and compared. Methods We retrospectively reviewed the medical records of 72 patients with IXT. All the patients had undergone the initial strabismus surgery between April 2015 and October 2018 and had been preoperatively tested by both PAT and MO performed on different days for 30 and 60 min. Near and distance deviations after 30 and 60 min of PAT and MO were compared to their baseline measurements obtained immediately after prism wear and before occlusion by alternate prism cover test. The near/distance measurements and required test duration to reveal the maximum deviation angle were also compared between PAT and MO. Results Compared with the baseline, the near deviation by PAT significantly increased after 30 (P < 0.05) and 60 (P < 0.01) minutes but not the distance deviation. However, the increase after 30 min was not significant. By MO, neither near nor distance deviation showed a significant difference from the baseline after 30 and 60 min. PAT showed a significantly larger near deviation than MO at 30 and 60 min, but a larger distance deviation by PAT was only observed at 30 min. Conclusions In patients with basic and convergence insufficiency types of IXT, a 30-minute PAT appears to be more effective than MO in revealing the maximum angle of deviation before strabismus surgery.

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Maximum Temperature Through a Yttrium Stabilized Zirconia Ceramic After Er,Cr:YSGG Laser Irradiation

Current Dentistry ◽

10.2174/2542579x02999200806160149 ◽

2020 ◽

Vol 02 ◽

Author(s):

Laurel Stringer ◽

Sarah Malley ◽

Darrell M. Hutto ◽

Jason A. Griggs ◽

Susana M. Salazar Marocho

Keyword(s):

High Speed ◽

Potential Method ◽

Maximum Temperature ◽

Zirconia Ceramic ◽

Tooth Pulp ◽

Control Group ◽

Stabilized Zirconia ◽

Significant Difference ◽

Power Setting ◽

Group A

Background: The most common approach to remove yttria stabilized zirconia (YSZ) fixed-dental prostheses (FDPs) is by means of diamond burs attached to a high-speed handpiece. This process is time-consuming and destructive. The use of lasers over mechanical instrumentation for removal of FDPs can lead to efficient and predictable restoration retrievability. However, the heat produced might damage the tooth pulp (>42˚C). Objective: The purpose of this study was to determine the maximum temperature (T) reached during the use of different settings of the erbium, chromium:yttrium-scandium-gallium-garnet Er,Cr:YSGG laser through a YSZ ceramic. Methods: YSZ slices (1 mm thick) were assigned into 7 groups. For the control group, a diamond bur was used to cut a 1 mm groove into the YSZ slices. For the 6 experimental groups, the laser was operated at a constant combination of 33% water and 66% air during 30 s with two different power settings (W) at three frequencies (PPS), as follows (W/PPS): 2.5/20, 2.5/30, 2.5/45, 4.5/20, 4.5/30, 4.5/45. The T through the YSZ slice was recorded in degrees Celsius by using a digital thermometer with a K thermocouple. Results: The median T of the control group was 26.5˚C. The use of 4.5 W resulted in the median T (˚C) of 44.2 at 20 PPS, 53.3 at 30 PPS, and 58.9 at 45 PPS, while 2.5 W showed 34.6, 31.6, and 25.0 at 20, 30, and 45 PPS, respectively. KruskalWallis one-way ANOVA showed that within each power setting, the T was similar. The high power and lowest frequency (4.5/20) showed no significant difference from the 2.5 W settings and the control group. Conclusion: The lower power setting (2.5 W) is a potential method for the use of the Er,Cr:YSGG laser to debond YSZ structures. The higher power (4.5 W) with high frequencies (30 and 45 PPS) is unsuitable.

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Lignin-Containing Coatings for Packaging Materials—Pilot Trials

Polymers ◽

10.3390/polym13101595 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1595

Author(s):

Asif Javed ◽

Peter Rättö ◽

Lars Järnström ◽

Henrik Ullsten

Keyword(s):

High Speed ◽

Water Solubility ◽

Transmission Rate ◽

Kraft Lignin ◽

Packaging Materials ◽

Water Contact ◽

Pilot Trials ◽

Significant Difference ◽

Ph Level ◽

Ammonium Zirconium Carbonate

One severe weakness of most biopolymers, in terms of their use as packaging materials, is their relatively high solubility in water. The addition of kraft lignin to starch coating formulations has been shown to reduce the water solubility of starch in dry coatings. However, lignin may also migrate into aqueous solutions. For this paper, kraft lignin isolated using the LignoBoost process was used in order to examine the effect of pH level on the solubility of lignin with and without ammonium zirconium carbonate (AZC). Machine-glazed (MG) paper was coated in a pilot coating machine, with the moving substrate at high speed, and laboratory-coated samples were used as a reference when measuring defects (number of pinholes). Kraft lignin became soluble in water at lower pH levels when starch was added to the solution, due to the interactions between starch and lignin. This made it possible to lower the pH of the coating solutions, resulting in increased water stability of the dry samples; that is, the migration of lignin to the model liquids decreased when the pH of the coating solutions was reduced. No significant difference was observed in the water vapor transmission rate (WVTR) between high and low pH for the pilot-coated samples. The addition of AZC to the formulation reduced the migration of lignin from the coatings to the model liquids and led to an increase in the water contact angle, but also increased the number of pinholes in the pilot-coated samples.

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A Fast and Effective System for Analysis of Optokinetic Waveforms with a Low-Cost Eye Tracking Device

Healthcare ◽

10.3390/healthcare9010010 ◽

2020 ◽

Vol 9 (1) ◽

pp. 10

Author(s):

Chong-Bin Tsai ◽

Wei-Yu Hung ◽

Wei-Yen Hsu

Keyword(s):

Eye Movements ◽

Eye Tracking ◽

Eye Movement ◽

Low Cost ◽

Saccadic Eye Movements ◽

Slow Phase ◽

Eye Tracker ◽

Effective System ◽

Tracking Device ◽

Traditional Approaches

Optokinetic nystagmus (OKN) is an involuntary eye movement induced by motion of a large proportion of the visual field. It consists of a “slow phase (SP)” with eye movements in the same direction as the movement of the pattern and a “fast phase (FP)” with saccadic eye movements in the opposite direction. Study of OKN can reveal valuable information in ophthalmology, neurology and psychology. However, the current commercially available high-resolution and research-grade eye tracker is usually expensive. Methods & Results: We developed a novel fast and effective system combined with a low-cost eye tracking device to accurately quantitatively measure OKN eye movement. Conclusions: The experimental results indicate that the proposed method achieves fast and promising results in comparisons with several traditional approaches.

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