Binocular Eye Tracking Research Articles

Examining gaze behavior in undergraduate students and educators during the evaluation of tooth preparation: an eye-tracking study

BackgroundGaze behavior can serve as an objective tool in undergraduate pre-clinical dental education, helping to identify key areas of interest and common pitfalls in the routine evaluation of tooth preparations. Therefore, this study aimed to investigate the gaze behavior of undergraduate dental students and dental educators while evaluating a single crown tooth preparation.MethodsThirty-five participants volunteered to participate in the study and were divided into a novice group (dental students, n = 18) and an expert group (dental educators, n = 17). Each participant wore a binocular eye-tracking device, and the total duration of fixation was evaluated as a metric to study the gaze behavior. Sixty photographs of twenty different tooth preparations in three different views (buccal, lingual, and occlusal) were prepared and displayed during the experimental session. The participants were asked to rate the tooth preparations on a 100 mm visual analog rating scale and were also asked to determine whether each tooth preparation was ready to make an impression. Each view was divided into different areas of interest. Statistical analysis was performed with a three-way analysis of the variance model with repeated measures.ResultsBased on the participants’ mean rates, the “best” and the “worst” tooth preparations were selected for analysis. The results showed a significantly longer time to decision in the novices compared to the experts (P = 0.003) and a significantly longer time to decision for both the groups in the best tooth preparation compared to the worst tooth preparation (P = 0.002). Statistical analysis also showed a significantly longer total duration of fixations in the margin compared to all other conditions for both the buccal (P < 0.012) and lingual (P < 0.001) views.ConclusionsThe current study showed distinct differences in gaze behavior between the novices and the experts during the evaluation of single crown tooth preparation. Understanding differences in gaze behavior between undergraduate dental students and dental educators could help improve tooth preparation skills and provide constructive customized feedback.

Elevated Smooth Pursuit Gain in Collegiate Athletes with Sport-related Concussion Immediately Following Injury.

Although there is evidence that sport-related concussion (SRC) affects oculomotor function and perceptual ability, experiments are often poorly controlled and are not replicable. This study aims to test the hypothesis that there are decreased values when assessing oculomotor impairment indicating poorer performance in SRC patients. Fifteen DI athletes presenting with SRC (7 females, 8 males) and 15 student volunteers (CON) (12 females, 3 males) completed a dynamic visual acuity (DVA) task that involved answering the direction of a moving stimulus (Landolt C) while wearing a head-mounted binocular eye tracker. There were 120 trials total with 60 trials presenting at 30º per second and 60 presenting at 90º per second. Various eye movement measurements, including horizontal smooth pursuit eye movements (SPEM) gain and saccadic peak velocity, were analyzed between groups using univariate ANOVAs. Saccade count in SPEM trials, accuracy, and vision were analyzed using Kruskal-Wallis tests. There was no statistical difference in saccadic peak velocity: SRC = 414.7 42º/s, CON = 406.6 40.6º/s. A significant difference was found between SRC patients and healthy controls in horizontal SPEM gain (SRC = 0.9 0.04, CON = 0.86 0.03, F(1,28) = 7.243, P = 0.012) indicating that patients demonstrated compensatory eye movements when tracking the target. There were significantly more saccades in all SPEM trials (P = 0.001). SRCoculomotor deficits manifest as elevated horizontal SPEM gain when assessed within 48 hours of injury and compared to healthy controls within the same age range. SRC demonstrates altered oculomotor ability. While accurate in tracking a stimulus, SRC patients may conduct less controlled eye movements.

86‐3: Binocular Camera Eye Tracking Algorithm for Naked Eye 3D Display

Through real‐time acquisition of eye position using eye tracking, viewers can experience stereoscopic scenes from the naked eye 3D display. This paper proposes binocular camera eye tracking method that utilizes disparity to perceive the actual inter‐pupillary distance of different users. This method estimates the head posture based on facial landmark points and exploits camera projection to determine the spatial coordinate of the pupil. Furthermore, collaborative filtering approach is introduced to mitigate the jitter in pupil position. The experimental results demonstrate that the proposed algorithm enhances the performance in eye tracking compared to monocular method.

Contributed Session II: Binocular combination of the pupil response depends on photoreceptor pathway.

The pupillary light response is driven by three classes of retinal photoreceptor. Cones and rods are involved in the initial constriction of the pupil, whereas melanopsin-containing intrinsically photosensitive Retinal Ganglion Cells (ipRGCs) maintain constriction over longer timescales. Previous work has characterized the contributions of photoreceptor signals to pupil control, but relatively little is known about binocular combination of these signals when simultaneously stimulating the retina in both eyes. We measured changes in pupil size in 48 participants using a binocular eye-tracker, targeting specific photoreceptor classes with a binocular 10-primary light engine and the silent substitution method. We stimulated the periphery of the retina using light flickering at 0.4 and 0.5 Hz. Participants viewed a disc of either achromatic flickering light, or contrast modulations that targeted the ipRGCs, or the opponent colour pathways L-M or S-(L+M). Using a modified virtual reality headset, we presented the stimuli at a range of modulation amplitudes in three different ocular configurations: monocular, binocular, and dichoptic. We obtained clear pupil responses at both the first and the second harmonic frequencies. Suppression levels differed across conditions with the strongest suppression measured for the L-M condition. We account for the results in a single modelling framework where the weight of interocular suppression determines the binocular combination properties.

Examining the exposure-reception-retention link in realistic communication environments via VR and eye-tracking: The VR billboard paradigm.

Exposure is key to message effects. No effects can ensue if a health, political, or commercial message is not noticed. Yet, existing research in communication, advertising, and related disciplines often measures 'opportunities for exposure' at an aggregate level, whereas knowing whether recipients were 'actually exposed' to a message requires a micro-level approach. Micro-level research, on the other hand, focuses on message processing and retention, takes place under highly controlled laboratory conditions with forced message exposure, and largely ignores how recipients attend selectively to messages under more natural conditions. Eye-tracking enables us to assess actual exposure, but its previous applications were restricted to screen-based reading paradigms lacking ecological validity or field studies that suffer from limited experimental control. Our solution is to measure eye-tracking within an immersive VR environment that creates the message delivery and reception context. Specifically, we simulate a car ride down a highway alongside which billboards are placed. The VR headset (HP Omnicept Pro) provides an interactive 3D view of the environment and holds a seamlessly integrated binocular eye tracker that records the drivers' gaze and detects all fixations on the billboards. This allows us to quantify the nexus between exposure and reception rigorously, and to link our measures to subsequent memory, i.e., whether messages were remembered, forgotten, or not even encoded. An empirical study shows that incidental memory for messages differs based on participants' gaze behavior while passing the billboards. The study further shows how an experimental manipulation of attentional demands directly impacts drivers' gaze behavior and memory. We discuss the large potential of this paradigm to quantify exposure and message reception in realistic communication environments and the equally promising applications in new media contexts (e.g., the Metaverse).

Passive identification of subjective preferences toward individual items using eye-tracking in a virtual reality environment

AbstractThe usage of virtual reality (VR) has been growing in many fields of research and therapy thanks to its immersive and gamified nature. Detection of the users’ subjective experience is thus essential for the effective personalization of content. Eye-tracking (ET) data and specifically gaze, in two-dimensional tasks, has been linked to value-based choices and emotional states. Therefore, here we aimed to develop a method for passive identification of subjective preferences based on ET data collected during a VR experience. For this purpose, we developed a naturalistic dynamic VR task where participants searched and looked at complex objects of pets and their control shapes that appeared in pre-defined locations in random order. At the end of the task, participants ranked their preference, valence, and arousal of the items they saw during the task. ET data was recorded using a built-in binocular eye-tracker within the VR headset. We found that the gaze behavior features of the median distance of gaze from the center of objects and the median gaze scan speed showed a significant interaction with object type (pets/shapes), as well as a significant positive relation to preference and valence rankings of pets. Our results suggest that these gaze behavior features could be used as passive biomarkers for detecting individual preferences and pleasantness, and in the future may enable successful personalization of VR content in real-time for various applications such as optimization of psychiatric diagnosis and treatment sessions.

GazeBaseVR, a large-scale, longitudinal, binocular eye-tracking dataset collected in virtual reality

We present GazeBaseVR, a large-scale, longitudinal, binocular eye-tracking (ET) dataset collected at 250 Hz with an ET-enabled virtual-reality (VR) headset. GazeBaseVR comprises 5,020 binocular recordings from a diverse population of 407 college-aged participants. Participants were recorded up to six times each over a 26-month period, each time performing a series of five different ET tasks: (1) a vergence task, (2) a horizontal smooth pursuit task, (3) a video-viewing task, (4) a self-paced reading task, and (5) a random oblique saccade task. Many of these participants have also been recorded for two previously published datasets with different ET devices, and 11 participants were recorded before and after COVID-19 infection and recovery. GazeBaseVR is suitable for a wide range of research on ET data in VR devices, especially eye movement biometrics due to its large population and longitudinal nature. In addition to ET data, additional participant details are provided to enable further research on topics such as fairness.

Quantitative assessment of eye movements using a binocular paradigm: comparison among amblyopic, recovered amblyopic and normal children

BackgroundTo investigate the eye movement functions in children with amblyopia and recovered amblyopia by a binocular eye-tracking paradigm.MethodsEye movements of 135 pediatric subjects (age range: 4–14 years), including 45 amblyopic children, 45 recovered amblyopic children and 45 age-similar normal controls, were recorded under binocular viewing with corrected refractive errors (if any). The deviation of gaze positions relative to the target location was recorded as the mean from both eyes. Main outcome measures included fixation deviations (degree) along horizontal and vertical axes in the sustained fixation test (Fix-X, Fix-Y) and visually guided saccade test (Sac-X, Sac-Y), which were compared across the three groups and between each two groups.ResultsAll the four deviations were significantly larger in the amblyopia group compared to the other two groups, indicating increased inaccuracy of sustained and post-saccadic fixations in amblyopia. However, there was no significant difference in deviations between recovered amblyopic children and normal controls. Repeated measures showed similar results overall and within each group. Mild to moderate amblyopes and severe amblyopes did not differ in the four deviations. No significant interaction was found between subject groups and clinical characteristics (age, refractive status, and anisometropia).ConclusionAmblyopic children have poor eye movement functions with increased inaccuracy of sustained and post-saccadic fixations, which appear to be restored in children with recovered amblyopia. Binocular assessment of eye movements provides valuable indicators of functional recovery in amblyopia.

High-fidelity eye, head, body, and world tracking with a wearable device

We describe the design and performance of a high-fidelity wearable head-, body-, and eye-tracking system that offers significant improvement over previous such devices. This device’s sensors include a binocular eye tracker, an RGB-D scene camera, a high-frame-rate scene camera, and two visual odometry sensors, for a total of ten cameras, which we synchronize and record from with a data rate of over 700 MB/s. The sensors are operated by a mini-PC optimized for fast data collection, and powered by a small battery pack. The device records a subject’s eye, head, and body positions, simultaneously with RGB and depth data from the subject’s visual environment, measured with high spatial and temporal resolution. The headset weighs only 1.4 kg, and the backpack with batteries 3.9 kg. The device can be comfortably worn by the subject, allowing a high degree of mobility. Together, this system overcomes many limitations of previous such systems, allowing high-fidelity characterization of the dynamics of natural vision.

Objective Infrared Eye Tracking Aids in the Identification of Concussion-Related Vision Disorders in Adolescen Ts with Persistent Post-Concussive Symptoms

Background:The visio-vestibular examination (VVE) of smooth pursuit, saccades, vestibulo-oculomotor reflex, near point of convergence (NPC), accommodative amplitude (AA), and complex tandem gait, has enhanced the physical examination of concussed individuals. The EyeBOX is a FDA-approved device for the diagnosis of concussion.Hypothesis:The goal of this investigation was to determine the diagnostic accuracy for concussion-related vision disorders of infrared eye-tracking via the EyeBOX.Methods:A cross-sectional study of 112 adolescents ages 11-18 years of age experiencing persistent post-concussion symptoms 4-12 weeks after concussion was conducted. All subjects had a clinical visio-vestibular examination (VVE) with a sports medicine physician, and a formal, comprehensive vision examination conducted by a pediatric developmental optometrist. A binocular eye tracking assessment was performed using the EyeBOX. Binocular pupil gaze positions are captured to ensure quality data acquisition and binocular movements in the X and Y axes are recorded at 500 Hz. Dynamic time series eye tracking data is acquired with 89 different metrics from eye movement in different planes recorded for each eye at 500 Hz captured over 220 seconds. From the time series data, a summary score, between 0 and 20, the BOX score, is generated.Logistic regression was used to estimate the association between each clinical VVE parameter and concussion-related vision diagnosis. Univariate and multivariate analyses were performed to determine the predictive ability of all VVE parameters to predict a concussion-related vision diagnosis. The area under the receiver-operator (ROC) curve was estimated by treating the linear predictor from the logistic regression as a continuous diagnostic parameter. A p-value is reported for the Wald test of whether a logistic regression coefficient differs from zero. Results:The clinical VVE variables had an AUC = 0.64 for tandem gait errors (p=0.06), 0.64 for monocular AA (p=0.01 for each), and 0.66 for NPC (p<0.01). A multivariable model including all nine VVE variables had predictive ability to identify concussion-related vision disorders in adolescents with persistent post-concussion symptoms with an AUC = 0.73. The BOX score alone had an AUC = 0.67 (p<0.01).Conclusions:The addition of the BOX score, a composite measure of objectively acquired eye tracking data, to the multivariable model with all nine dichotomous VVE variables added significant additional diagnostic ability (p<0.01), yielding an AUC = 0.81. The combination of a clinical visio-vestibular examination and objective infrared eye tracking has relevant diagnostic value, facilitating identification and treatment of concussion-related vision disorders.

Binocular coordination of children with dyslexia and typically developing children in linguistic and non-linguistic tasks: evidence from eye movements.

Given the increased evidence suggesting the presence of binocular coordination deficits in dyslexia, investigations of binocular eye movements are beneficial to clarify the underlying causes of reading difficulties. This systematic review aims to (a) synthesize the literature through the examination of binocular coordination in children with dyslexia by describing the normative development of stable binocular control and (b) outline future directions. Boolean expressions in the PubMed search were used to define papers. Following a literature search and selection process, 25 papers were included. Studies using binocular eye tracking during linguistic and nonlinguistic tasks in children with dyslexia and typical development 5-17years of age are reviewed. The studies reviewed provided consistent evidence of poor binocular coordination in children with dyslexia, but the results associated with different task characteristics were less consistent. The relation between binocular coordination deficits and reading difficulties needs to be further elucidated in longitudinal studies which may provide future treatments targeting the binocular viewing system in dyslexia.

Depth and Perspective Perception of Flat Images in Static and Dynamic Visual Scenes

The paper shows that a sense of depth can arise from two-dimensional (2D) scenes without the presence of a stereoscopic depth signal. Experimental information was obtained on three-dimensional (3D) visual perception of 2D static and dynamic scenes. The technique is based on fixing the conditions of eye movement during the perception of two-dimensional stimulus scenes. To obtain registration of the depth perception effects, they used volume and spatial perspective of 2D images (3D phenomenon), and a binocular eye tracker. The 3D phenomenon is identified using 3D raster images. It is assumed that the comparison of eye movements during a 3D raster image viewing allows you to identify uniquely the effects of the 3D phenomenon of stimulus planar scenes displayed on the monitor screen. The first part of the work shows the conditions for the emergence of a 3D phenomenon on two plots of dynamic and static scenes. The second part demonstrates the three-dimensional attributes of dynamic scenes with the highlighting of various video components. We emphasize that dynamic and static scenes are obtained directly from TV programs. The proposed graphical and mathematical method of analysis made it possible to show qualitatively the perception of the 3D phenomenon by KFU students and revealed the features of volume observation for planar images without the occurrence of binocular disparity.

Diagnostic accuracy of binocular eye tracking in the assessment of paraphilic disorders

Diagnostic accuracy of binocular eye tracking in the assessment of paraphilic disorders

A Novel Integrated Eye-Tracking System with Stereo Stimuli for 3D Gaze Estimation

Eye-tracking technology is increasingly used in applications such as 3D displays and human-computer interaction (HCI). However, most current eye trackers focus on 2D point-of-gaze (PoG) estimation and cannot provide accurate gaze depth. Concerning future applications such as HCI with 3D displays, we propose an integrated binocular eye-tracking device with stereo stimuli to provide highly accurate 3D PoG estimation. In our device, the 3D stereo imaging system can provide users with a friendly and immersive 3D visual experience without wearing any accessories. The eye-capturing system can directly record the users’ eye movements under 3D stimuli without disturbance, which can realize front views of eye images while ensuring the user’s wide field of view (FOV). A regression-based 3D eye-tracking model is built based on collected eye movement data under stereo stimuli. Our model estimates users’ 2D gaze with features defined by eye region landmarks and further estimates 3D gaze with a multi-source feature set constructed by comprehensive eye movement features and disparity features from stereo stimuli. Two test stereo scenes with different depths of field are designed to verify the model’s effectiveness. Experimental results of four-fold cross-validation show that the average error for 2D gaze estimation was 0.65°. For 3D gaze estimation, the average errors are 1.69 cm over the workspace volume 50 × 30 × 75 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> and 0.14 m over the workspace volume 2.4 × 4.0 × 7.9 m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> . Two preliminary validation experiments also demonstrate that our system has broad application prospects, such as 3D vision technologies and medical applications related to neurological diseases.

Gaze behavior during pedestrian interactions in a community environment: a real-world perspective.

Locomotor adaptations, as required for community walking, rely heavily on the sense of vision. Little is known, however, about gaze behavior during pedestrian interactions while ambulating in the community. Our objective was to characterize gaze behavior while walking in a community environment and interacting with pedestrians of different locations and directions. Twelve healthy young individuals were assessed as they walked in a shopping mall from a pre-set location to a goal located 20m ahead. Eye movements were recorded with a binocular eye-tracker and temporal distance factors were assessed using wearable sensors from a full-body motion capture system. Participants exhibited more numerous and longer gaze episodes on pedestrians (GEP) that were walking in the same direction as themselves vs. those that were in the opposite direction. The relative durations of GEPs, however, showed no significant differences between pedestrians walking in the same vs. opposite direction. Longer durations of GEPs were also observed for centrally located pedestrians compared to those located on either side, but this was the case only for pedestrians that were walking in the same direction as participants. In addition, pedestrians in the centre, and even more so those on the right, were fixated at farther distances compared to those on the left. Results indicate that healthy young individuals modulate their gaze behavior as a function of the location and direction of pedestrians when ambulating in a community environment. The observed modulation is interpreted as being caused by an interplay between collision risk, pedestrian visibility, presence of leaders and social conventions (right-sided circulation). Present results also establish baseline measures for the quantification of defective visuomotor strategies in individuals with mobility disorders.

A low-cost, high-performance video-based binocular eye tracker for psychophysical research.

We describe a high-performance, pupil-based binocular eye tracker that approaches the performance of a well-established commercial system, but at a fraction of the cost. The eye tracker is built from standard hardware components, and its software (written in Visual C++) can be easily implemented. Because of its fast and simple linear calibration scheme, the eye tracker performs best in the central 10 degrees of the visual field. The eye tracker possesses a number of useful features: (1) automated calibration simultaneously in both eyes while subjects fixate four fixation points sequentially on a computer screen, (2) automated realtime continuous analysis of measurement noise, (3) automated blink detection, (4) and realtime analysis of pupil centration artifacts. This last feature is critical because it is known that pupil diameter changes can be erroneously registered by pupil-based trackers as a change in eye position. We evaluated the performance of our system against that of a wellestablished commercial system using simultaneous measurements in 10 participants. We propose our low-cost eye tracker as a promising resource for studies of binocular eye movements.

GazeGuide: An Eye-Gaze-Guided Active Immersive UAV Camera

Over the years, gaze input modality has been an easy and demanding human–computer interaction (HCI) method for various applications. The research of gaze-based interactive applications has advanced considerably, as HCIs are no longer constrained to traditional input devices. In this paper, we propose a novel immersive eye-gaze-guided camera (called GazeGuide) that can seamlessly control the movements of a camera mounted on an unmanned aerial vehicle (UAV) from the eye-gaze of a remote user. The video stream captured by the camera is fed into a head-mounted display (HMD) with a binocular eye tracker. The user’s eye-gaze is the sole input modality to maneuver the camera. A user study was conducted considering the static and moving targets of interest in a three-dimensional (3D) space to evaluate the proposed framework. GazeGuide was compared with a state-of-the-art input modality remote controller. The qualitative and quantitative results showed that the proposed GazeGuide performed significantly better than the remote controller.

Role of vergence eye movements in the visual recognition of long time duration.

When viewing dichoptic stimuli in long time duration, visual percepts are always the alternation between the left and right eye inputs, while not the combination. This is known as binocular rivalry. An efficient coding theory reported that binocular visual inputs can be combined into binocular summation (S+) and difference (S-) channels in V1 brain area. In this study, we used specially designed stimuli as the previous study, in which monocular inputs caused ambiguous percepts, but S+ and S- channels had unambiguous percepts. We aim to investigate whether the visual percepts alter between S+ and S- channels in long time duration and whether vergence eye movements are involved in the process. To do so, the stimuli were presented in 300-s time duration in a trial, and a binocular eye tracker was used to record eye information. Participants' real-time behavioral responses about the visual percepts and binocular information were recorded simultaneously. The results show there are perceptual flips between S+ and S- channels in both central and long time viewing conditions. More importantly, in central vision there are vergence eye movements before perceptual flips, suggesting the involvement of high level visual attention; the time of a perceptual flip from S+ is shorter than that of a flip from S-, which might be due to different involvements of visual attention, indicating a bias of feedback connection from higher brain areas for visual attention to S+ channel. Since S+ and S- dominated signals can be carried by different types of binocular neurons, our results provide new insights into high level visual attention and binocular neurons in V1 brain area by using specially designed dichoptic stimuli and eye vergence as measuring tools.

Prospects for the use of a binocular eye tracking system for the diagnosis of pedophilic disorder

The assessment of pedophilic disorder is one of the most complicated problems in forensic psychiatric practice. To evaluate the use of eye tracking to identify pedophilic disorder. One hundred people were stratified into a group of men with pedophilic disorder (n=43) and a group of people without clinical signs of pedophilia (n=57). Clinical, psychopathological, sexological and psychophysiological methods were used. Within the framework of a psychophysiological method, normative and deviant erotic stimuli were presented with simultaneous eye gaze recording. Methodological requirements to create the diagnostic visual tests, in the development of which the stimulus material should be highly standardized and take into account the color spectrum, size, content, as well as the emotional richness of the images, were suggested. Moreover, it was found that for the detection of paraphilic interest, it was very important to assess attention (involuntary and voluntary), based on the study of fixation activity: high rates of the total stimulus viewing time, duration of the first fixation, average duration of fixations and index of fixation activity indicate a high level of attention to the exposed deviant stimuli in subjects with pedophilic disorder, which shows their greater importance in comparison with normative stimuli. However, the individual analysis of the data should take into account not only individual physiological indicators, but also their combination, since an oculomotor activity is significantly influenced by internal and external factors. The obtained data suggest that eye tracking is a very promising diagnostic method to identify paraphilic disorders.

Pupil Function in Pseudophakia: Proximal Miosis Behavior and Optical Influence

The pseudophakic eye lacks the ability to produce a refractive change in response to object proximity. Thus, individual anatomical features such as the pupil size play an important role in achieving functional vision levels. In this work, the range of pupil sizes at varying object distance was measured in pseudophakic participants. Furthermore, the impact of the measured values on eye optical quality was investigated using a computer simulation model. A binocular eye-tracker was used to measure the participants’ pupil sizes at six object distances, ranging from 0.33 m (i.e., vergence of 3.00 D) to 3.00 m (i.e., vergence of 0.33 D), while observing a Maltese cross with a constant angular size of 1 ∘ . In total, 58 pseudophakic participants were enrolled in this study (age mean ± standard deviation: 70.5 ± 11.3 years). The effects of object distance and age on pupil size variation were investigated using linear mixed effects regression models. Age was found to have a small contribution to individual variability. The mean infinite distance pupil size (intercept) was 4.45 ( 95 % CI: 2.74, 6.17) mm and the mean proximal miosis (slope) was − 0.23 ( 95 % CI: −0.53, 0.08) mm/D. The visual acuity (VA) estimation for a distant object ranged from − 0.1 logMAR (smallest pupil) to 0.04 logMAR (largest pupil) and the near VA ( 0.33 m) when mean proximal miosis was considered ranged from 0.28 logMAR (smallest pupil) to 0.42 logMAR (largest pupil). When mean distance pupil was considered, proximal miosis individual variability produced a variation of 0.04 logMAR for the near object and negligible variation for the distant object. These results support the importance of distance pupil size measurement for the prediction of visual performance in pseudophakia, while suggesting that proximal miosis has a negligible impact in VA variability.