Larger Pupil Size Research Articles

Atypical attention and saccade vigor in post-traumatic stress disorder

Effective attention control is essential for behavioral adaptation to different environmental contexts. In Post-traumatic Stress Disorder (PTSD) altered attention has been described in trauma-related and other emotional contexts. Nevertheless, atypical attention is also seen with neutral stimuli. The mechanisms of attention alterations in PTSD associated with neutral stimuli are poorly understood.The present study investigates alerting and orienting responses in PTSD participants using emotionally neutral stimuli in a saccade eye movement task incorporating both spatially predictable and temporally unpredictable conditions. We studied 23 PTSD patients and 27 Non-PTSD controls, using repeated-measures mixed modeling to estimate group and task condition differences in behavioral and psychophysiological measures. We explored the relationships among saccade characteristics, pupil size, and PTSD symptoms, including CAPS hypervigilance scores. PTSD, compared to Non-PTSD, participants showed differences in their saccade ‘main sequence’, reflected by higher peak velocities adjusted for amplitude. PTSD participants had smaller primary position errors in the unpredictable saccade condition. They also exhibited greater hyperarousal, reflected by larger pupil size during fixation that was greater in the unpredictable condition.Our results suggest that a heightened state of arousal and hypervigilance in PTSD leads to a state of atypical attention bias, even in emotionally neutral contexts. These differences may reflect higher saccade vigor. The observed differences suggest atypical attention in PTSD, which goes beyond possible distraction associated with emotional or threat-related stimuli.

Gaze-based human intention prediction in the hybrid foraging search task

An agent’s ability to predict a human’s intention can facilitate the effectiveness of a human-agent team. The aim of this study was to explore the feasibility of predicting human intention in the hybrid foraging search task using eye gaze data and machine learning. In the hybrid foraging search paradigm, the human performs searches in patches and decides to stay and exploit a patch or to leave and explore another patch. Researchers have modeled the “patch-leaving problem” on the collective level using the marginal value theorem. However, few have attempted to predict the exact moment when the human will leave. In the current study, 40 participants performed the hybrid foraging search task while eye gaze data were collected with an eye-tracker. The leaving intention was associated with larger pupil size, shorter average fixation duration, larger number of fixations, longer saccade amplitude, and faster saccade velocity compared to the searching intention. A cross-subject machine learning model with an artificial neural network algorithm was able to predict whether a participant would leave the current patch with up to 78% accuracy with a 2-second data analysis window. The length of the data analysis window did not significantly affect prediction accuracy. Furthermore, the earlier the behavior prediction was made, the lower the reliability of the prediction. These results demonstrate that eye gaze features and machine learning algorithms are useful in predicting human intention in visual search tasks.

Task-evoked pupillary responses as potential biomarkers of mild cognitive impairment.

Eye movement alterations are effective biomarkers for Alzheimer's disease (AD). This study examines task-evoked pupillary responses (TEPRs) as potential biomarkers of the mild cognitive impairment (MCI), the symptomatic stage preceding AD. The prospective cohort study included 213 MCI patients and 514 cognitively normal controls (CNs). Participants performed a prosaccade (PS) or antisaccade (AS) task while their eye movements were tracked using a Tobii Pro Spectrum system. The CNs showed unique TEPRs linked to better performance, characterized by larger baselines, greater PS target-onset variability, and smaller AS target-onset variability. Conversely, for MCI patients, better performance was linked to larger AS target-onset sizes. Furthermore, MCI patients displayed reduced dilation during the cue and target-onset periods compared to CNs. MCI patients showed altered pupillary response patterns associated with cognitive task performance, highlighting the potential of oculomotor changes as a biomarker for early cognitive decline. MCI patients displayed markedly smaller pupil dilation than CNs in response to cue and target stimuli.For MCI patients, larger pupil size upon target appearance during antisaccades correlated with better performance.Faster and more consistent prosaccades were linked to better performance in both groups.For MCI patients, the association between longer AS latencies and better performance was more pronounced than in CNs.Combined analysis of TEPRs and saccade performances in a sizeable cohort strengthens the generalizability of our findings to the broader MCI population.

Pupillary Responses to Dot Patterns on a Human Face Background.

Dots on natural backgrounds can elicit significant pupillary constrictions within the entire image phase associated with parasympathetic activation, suggesting disgust rather than fear. Although studies have reported that dots on faces elicit stronger disgust than dots on non-face backgrounds, it remains unclear whether dots on a face elicit stronger pupil constrictions than non-face backgrounds. Pupillometry was used while viewing dots on faces and compared with luminance- and spatial frequency-controlled images (dots on phase-scrambled faces) and luminance-controlled images (face only, phase-scrambled faces). Relative pupillary constrictions were elicited when dots were placed on faces and phase-scrambled faces; however, the response to dots on faces did not differ significantly from that to the control stimuli. Approximately 3-5 s after stimulus onset, pupillary responses to dots on faces recovered to baseline faster than those to dots on phase-scrambled faces with a larger pupil size. The initial pupillary constrictions observed are consistent with those in response to dots on natural backgrounds, suggesting that regardless of the background, dots may stimulate parasympathetic activation and elicit disgust rather than fear. The faster recovery from the pupil constriction and larger pupil size in the later phase may be caused by a dynamic balance between the sympathetic and parasympathetic neuronal activities.

Intraoperative Cognitive Load Differences between Trainees and Attending Surgeons

Background/Objective: Cognitive load (CL) is the amount of mental effort and resources required to complete a task and process information in the working memory. In a surgical setting, high CL decreases attention to critical details, and slows down decision-making, increasing errors which can compromise patient safety. Our aim was to determine if CL differences exist between trainees and experienced attending surgeons. Such differences could inform readiness for trainee autonomy and training paradigms.
 Methods: Eye trackers were used by attending general surgeons and trainees during robotic gastrointestinal procedures to determine their CL. Average fixation rate (AFR), fixation to saccade (F:S) ratio, and change in pupil size, were recorded and compared between attending surgeons and trainees to determine differences in intraoperative cognitive load.
 Results: Three attendings and three trainees participated. While operating, trainees had a lower AFR (M=0.775, SD= 0.093) and a lower F:S (M=0.497, SD=0.102) compared to attendings (M=0.842, SD=0.152 and M=0.592, SD=0.243, respectively). Both trainees and attendings had a larger pupil size (M=4.29, SD=0.773 and M=3.63, SD=0.077, respectively) while operating compared to their pupil size while not operating (M=4.057, SD=0.821 and M=3.496, SD=0.059, respectively.
 Conclusion and Potential Impact:In this pilot study, we determined eye tracking metrics can be used to detect differences in intraoperative CL between trainees and attending surgeons and while they were operating or observing. Further research should determine methods that decrease CL of trainees.

Pupillometry to show stress release during equine sports massage therapy

Anecdotal reports state that wellness treatments for horses, such as massage therapy, relaxes the treated animal. Massage therapists and horse owners typically report an ”improvement” without verifying or quantifying the treatment results. This paper shows that the effect of wellness treatment and stress release can be measured with pupillometry. One of the horse’s pupils was photographed at the beginning and end of the treatment to determine the changes in the balance between the sympathetic and parasympathetic system activities. The owners assigned horses to two experimental groups: animals receiving a massage (N = 18) and horses standing with a person next to the horse for the time of a massage in the stable lane (N = 10). Six animals in the experimental group were excluded from the analysis because the pupils could not be traced. We opened the images of the pupil with Fiji (ImageJ) and used the elliptical selection tool to measure the pupils’ and iris’ areas. The ratio between the pupils’ aperture and the iris’ area was a normalized measure for pupil size. At the end of the experiment, we compared the normalized size of the pupils with a two-tailed paired t-test within groups and a two-tailed t-test between groups. For the experimental group, it was before and after the treatment, and for the control group, before and after the horse was placed in the stable lane. Comparisons between the experimental and control groups were made at the procedure's beginning and end. The treatment significantly decreased the normalized pupil area in the experimental group, on average, by a factor of 0.78 ± 0.15 (P = 0.042). For the horses in the control group, the pupil size increased, on average, by a factor of 1.14 ± 018. Changes were statistically not significant (P = 0.19). The initial pupil size of the horses in the experimental group was 1.88 times larger than that in the control group. After the treatment, the difference was reduced to a factor of 1.25. At the beginning of the experiment, the horses in the experimental group had, on average, larger pupil sizes than the horses in the control group, indicating that the horses in the experimental group were more stressed before the treatment than the control animals. The observed changes in pupil size in the experimental group likely resulted from enhanced parasympathetic and diminished sympathetic activity resulting from the treatment. Observed changes in pupil size agree with the anecdotal horse owner reports and the therapist’s treatment notes.

Pupil size shows diminished increases on verbal fluency tasks in patients with behavioral-variant-frontotemporal dementia

While behavioral variant frontotemporal dementia (bvFTD) is mainly associated with behavioral, social, cognitive, and emotional impairments, impairments in language can also be observed. We thus assessed whether linguistic processing can be assessed by pupillometry. We invited patients with bvTFD and control participants to perform a verbal fluency task, a category fluency task and, as a control task, to count aloud. During the three tasks, pupil size was monitored using eye-tracking glasses. Results demonstrated smaller pupil size on letter and category verbal fluency tasks, as well as during counting, in patients with bvFTD compared with control participants. However, larger pupil size was observed during verbal fluency tasks compared to counting in both patients with bvFTD and control participants. There were the no significant differences on pupil size between letter and category fluency tasks in any population. Finally, patients with bvFTD compared to control participants had lower verbal fluency. Taken together, these findings demonstrate how verbal fluency may decrease pupil size less in patients with bvFTD than controls, and how pupillometry can be used to follow linguistic processing in patients with frontal lobe impairments.

Social stress in an interaction with artificial agents in virtual reality: Effects of ostracism and underlying psychopathology

Social stress can emerge from situational as well as dispositional factors. Here we tested in direct juxtaposition how ostracism in a Cyberball game and underlying psychopathology levels both influence subjective and objective stress markers in an interaction with artificial agents in virtual reality (VR) in 80 participants from a student population. Ostracism led to moderately enhanced subjective stress and negative mood but not to alterations on objective markers of stress. By contrast, underlying psychopathology levels were associated with substantially stronger alterations on subjective stress markers and were additionally associated with reduced eye gaze at virtual agents' heads, larger pupil size, larger high-frequency pupil-size variability, higher heart rate and reduced high-frequency heart-rate variability. Effects for social anxiety, general anxiety and depression levels were overall similar with largest effects on objective stress markers linked to general anxiety. These findings contest the suitability of the Cyberball game as a model for real-life ostracism but demonstrate the utility of gaze and physiological data in predicting psychopathology levels during interactions in VR. These findings furthermore highlight the need for data security solutions when using social VR applications where rich data streams are exposed publicly.

Motor synchronization and impulsivity in pediatric borderline personality disorder with and without attention-deficit hyperactivity disorder: an eye-tracking study of saccade, blink and pupil behavior.

Shifting motor actions from reflexively reacting to an environmental stimulus to predicting it allows for smooth synchronization of behavior with the outside world. This shift relies on the identification of patterns within the stimulus - knowing when a stimulus is predictable and when it is not - and launching motor actions accordingly. Failure to identify predictable stimuli results in movement delays whereas failure to recognize unpredictable stimuli results in early movements with incomplete information that can result in errors. Here we used a metronome task, combined with video-based eye-tracking, to quantify temporal predictive learning and performance to regularly paced visual targets at 5 different interstimulus intervals (ISIs). We compared these results to the random task where the timing of the target was randomized at each target step. We completed these tasks in female pediatric psychiatry patients (age range: 11-18 years) with borderline personality disorder (BPD) symptoms, with (n = 22) and without (n = 23) a comorbid attention-deficit hyperactivity disorder (ADHD) diagnosis, against controls (n = 35). Compared to controls, BPD and ADHD/BPD cohorts showed no differences in their predictive saccade performance to metronome targets, however, when targets were random ADHD/BPD participants made significantly more anticipatory saccades (i.e., guesses of target arrival). The ADHD/BPD group also significantly increased their blink rate and pupil size when initiating movements to predictable versus unpredictable targets, likely a reflection of increased neural effort for motor synchronization. BPD and ADHD/BPD groups showed increased sympathetic tone evidenced by larger pupil sizes than controls. Together, these results support normal temporal motor prediction in BPD with and without ADHD, reduced response inhibition in BPD with comorbid ADHD, and increased pupil sizes in BPD patients. Further these results emphasize the importance of controlling for comorbid ADHD when querying BPD pathology.

Effects of Temporal Light Modulation on Cognitive Performance,Eye Movements, and Brain Function

ABSTRACT Temporal light modulation (TLM) describes variations in light output from a light source or lighting system and can be a characteristic of their normal operation. TLM at 100 or 120 Hz can disrupt eye movements and reduce visual performance compared to 40 kHz, but little is known of the effects between those frequencies. Such evidence could provide the basis for lighting product and application standards to support the development of energy-efficient lighting systems. This repeated-measures experiment compared the effects of three stimuli (no TLM [DC], 100 Hz, and 500 Hz [both rectangular-wave, 100% modulation depth, 50% duty cycle]) on state anxiety, eye movements (blinks, saccades, fixations, and pupil size), cognitive performance (Stroop task and sentence reading speed), and visual event-related potentials (ERPs). Post-processing of EEG data included dipole source analysis and estimates of source dipole strength. TLM at 100 Hz was associated with larger pupil sizes and greater ERP dipole strength during 100 Hz exposure than no TLM, particularly in the right hemisphere. Cognitive interference was lower for 500 Hz TLM than 100 Hz. State anxiety was unaffected. The addition of TLM to the light source signal increased arousal and altered brain activity; at the highest frequency tested here this reduced cognitive interference. Arousal theory and stochastic facilitation can provide possible explanations.

Contribution of listening effort and cognitive processing to psychometric functions during adolescence and young adulthood

Hearing and listening are critical to how adolescents communicate, learn new information, and engage with technology and culture. However, performance on auditory perceptual tasks takes a long time to mature. Age-related improvements in executive functions and other cognitive functions likely contribute to this long developmental trajectory. To examine how listening effort and cognition relate to psychometric functions on auditory perceptual tasks in adolescents and young adults, we used the method of constant stimuli to test 10- to 23-year-olds on frequency discrimination, temporal interval discrimination, and gap detection. During task performance, an eye tracker was used to measure pupil size and blink rate as proxies for listening effort or engagement. Typically, larger pupil size and fewer blinks are associated with higher engagement. All listeners also completed a battery of cognitive tests including tests of verbal and nonverbal reasoning, working memory, processing speed, and attention. We will demonstrate any changes in the estimated thresholds and psychometric function slopes during adolescence and will relate these developmental changes to individual differences in listening effort and cognition. [Work funded by NIDCD.]

Scheimpflug-Derived Corneal Lower and Higher Order Aberrations Post Intrastromal Corneal Ring Segments for Keratoconus.

Intrastromal corneal ring segments (ICRS) improve corneal topographic symmetry and reduce corneal aberrations through regularization of the corneal surface, thereby functioning as a viable surgical intervention for patients with keratoconus. This study aims to evaluate changes in lower- (LOAs) and higher-order aberrations (HOAs) amongst varying pupil sizes pre- and post- ICRS implantation in keratoconus patients. We specifically investigate the impact of pupil size on total corneal HOAs up to the 6th order. Twenty-one eyes that underwent ICRS implantation were included in this prospective interventional study. LOAs and HOAs measurements at the 6 mm, 4 mm, and 2 mm pupil diameters were collected preoperatively and at 6 months postoperatively using the Zernicke analysis function on a Scheimpflug device. ICRS implantation demonstrated a statistically significant effect in vertical coma with a -0.23 reduction (p = 0.015) for a 4 mm pupil size and a -1.384 reduction (p < 0.001) for 6 mm, with no significant effect at 2 mm. Horizontal coma, astigmatism 0°, astigmatism 45°, trefoil 5th order 30°, and RMS HOA demonstrated significant reductions at 4 mm or 6 mm pupil sizes but not at 2 mm. Our analysis demonstrates a favorable effect of ICRS implantation on larger pupil sizes, suggesting the importance of pupil size as it correlates with HOAs reduction.

Pupil size effect on binocular summation for visual acuity and light disturbance.

Smaller pupil size under binocular conditions could justify partially the improvement of visual performance when compared to monocular conditions. The purpose of this study was to assess the binocular summation for increasing levels of spherical and cylindrical defocus when the pupil size factor is ruled out as a confounding factor. Fifteen young subjects were recruited in this crossover study. Light disturbance index (LDI) was evaluated with the light disturbance analyzer and low (LCDVA) and high (HCDVA) contrast visual acuity with the ETDRS test. Two positive spherical and cylindrical defocus levels (+ 1.5 and + 3.0 D) were used to induce a controlled degradation of the retinal image for two pupil sizes (3 and 5mm). Our results showed poorer visual performance in monocular than the binocular condition. An increasing deterioration was observed with the level of spherical defocus. Positive binocular summation for visual acuity was found in all the parameters studied and was stronger under larger pupil size and for higher levels of spherical defocus. It was observed a positive binocular summation for the LDI under all the conditions studied. Strong and significant correlations were found between LDI and LCDVA and between LDI and HCDVA for all the conditions. Higher correlations were obtained between disturbance index and visual acuity for spherical defocus compared to cylindrical. Binocular summation was observed under different conditions of spherical and cylindrical optical degradation of the image quality when the pupil size was fully controlled. This suggests that a neural factor is involved.

Interaural speech asymmetry predicts bilateral speech intelligibility but not listening effort in adults with bilateral cochlear implants.

Bilateral cochlear implants (BiCIs) can facilitate improved speech intelligibility in noise and sound localization abilities compared to a unilateral implant in individuals with bilateral severe to profound hearing loss. Still, many individuals with BiCIs do not benefit from binaural hearing to the same extent that normal hearing (NH) listeners do. For example, binaural redundancy, a speech intelligibility benefit derived from having access to duplicate copies of a signal, is highly variable among BiCI users. Additionally, patients with hearing loss commonly report elevated listening effort compared to NH listeners. There is some evidence to suggest that BiCIs may reduce listening effort compared to a unilateral CI, but the limited existing literature has not shown this consistently. Critically, no studies to date have investigated this question using pupillometry to quantify listening effort, where large pupil sizes indicate high effort and small pupil sizes indicate low effort. Thus, the present study aimed to build on existing literature by investigating the potential benefits of BiCIs for both speech intelligibility and listening effort. Twelve BiCI adults were tested in three listening conditions: Better Ear, Poorer Ear, and Bilateral. Stimuli were IEEE sentences presented from a loudspeaker at 0° azimuth in quiet. Participants were asked to repeat back the sentences, and responses were scored by an experimenter while changes in pupil dilation were measured. On average, participants demonstrated similar speech intelligibility in the Better Ear and Bilateral conditions, and significantly worse speech intelligibility in the Poorer Ear condition. Despite similar speech intelligibility in the Better Ear and Bilateral conditions, pupil dilation was significantly larger in the Bilateral condition. These results suggest that the BiCI users tested in this study did not demonstrate binaural redundancy in quiet. The large interaural speech asymmetries demonstrated by participants may have precluded them from obtaining binaural redundancy, as shown by the inverse relationship between the two variables. Further, participants did not obtain a release from effort when listening with two ears versus their better ear only. Instead, results indicate that bilateral listening elicited increased effort compared to better ear listening, which may be due to poor integration of asymmetric inputs.

Gaming for Training Voluntary Control of Pupil Size

Users can “voluntarily” control the size of their pupil by switching focus from a far target A (large pupil size) to a near target B (small pupil size), according to the pupillary accommodative response (PAR). Pupil size is governed by smooth muscles and has been suggested as communication pathway for patients affected by paralysis of skeletal muscles, such as in amyotrophic lateral sclerosis (ALS). We here present a video game that relies on PAR: a 2d side-scroller game where the user, by varying pupil size, controls the height at which a spaceship is moving aiming at colliding with bubbles to burst them and score points. The height at which the spaceship flies inversely depends on pupil area. The game is implemented on a Raspberry Pi board equipped with a IR camera and may record the time course of pupil size during the game, for off-line analysis. This application is intended as a tool to train and familiarize with the control of pupil size for alternative augmentative communication.

Small Pupils Lead to Lower Judgements of a Person’s Characteristics for Exaggerated, but Not for Realistic Pupils

Our eyes convey information about a person. The pupils may provide information regarding our emotional states when presented along with different emotional expressions. We examined the effects of pupil size and vergence on inferring other people’s characteristics in neutral expression eyes. Pupil sizes were manipulated by overlaying black disks onto the pupils of the original eye images. The disk area was then changed to create small, medium, and large pupils. Vergence was simulated by shifting the medium-sized disks nasally in one eye. Pupil sizes were exaggerated for Experiment 1 and followed values from the literature for Experiment 2. The first Purkinje image from the eye photos in Experiment 2 was kept to preserve image realism. The characteristics measured were sex, age, attractiveness, trustworthiness, intelligence, valence, and arousal. Participants completed one of two online experiments and rated eight eye pictures with differently sized pupils and with vergence eyes. Both experiments were identical except for the stimuli designs. Results from Experiment 1 revealed rating differences between pupil sizes for all characteristics except sex, age, and arousal. Specifically, eyes with extremely small pupil sizes and artificial vergence received the lowest ratings compared to medium and large pupil sizes. Results from Experiment 2 only indicated weak effects of pupil size and vergence, particularly for intelligence ratings. We conclude that the pupils can influence how characteristics of another person are perceived and may be regarded as important social signals in subconscious social interaction processes. However, the effects may be rather small for neutral expressions.

Pupil size as an indicator of cognitive activity in mild Alzheimer's disease.

It is well established that pupil activity indexes cognitive processing. For instance, research has consistently demonstrated that the pupil reacts to working memory span task performance. However, little is known about pupil reaction to cognitive processing in Alzheimer's Disease (AD). We thus investigated whether span tasks can modulate pupil size in patients with AD. We invited 24 patients with AD and 24 healthy older adults to perform backward and forward spans, as well as to count aloud in a control condition, while their pupil activity was recorded with eye tracking glasses. In patients with AD, analysis demonstrated larger pupil size during backward spans (M = 2.12, SD = .39) than during forward spans (M = 1.98, SD = .36) [t(23) = 3.22, p = .004], larger pupil size during forward spans than during counting (M = 1.67, SD = .33) [t(23) = 4.75, p < .001], as well as larger pupil size during backward spans than during counting [t(23) = 10.60, p < .001]. In control participants, analysis demonstrated larger pupil size during backward spans (M = 3.36, SD = .49) than during forward spans (M = 2.85, SD = .68) [t(23) = 5.82, p < .001], larger pupil size during forward spans than during counting (M = 2.09, SD = .62) [t(23) = 5.42, < .001], as well as larger pupil size during backward spans than during counting [t(23) = 9.70, p < .001]. Results also demonstrated a significant interaction effect between groups and conditions [F(2,92) = 16.63, p < .001]; in other words, patients with AD have shown fewer variations on the pupil size across the conditions compared to the control participants. The larger pupil size during backward spans, compared with forward spans or counting, can be attributed to the high cognitive load of backward spans. The modulation of pupil size, as observed across backward/forward spans and counting, can possibly be attributed to sympathetic/adrenergic and parasympathetic/cholinergic activities. Our study demonstrates the value of pupillometry as a potential biomarker of cognitive processing in AD.

Computerised dynamic posturography for postural control assessment in subjects wearing multifocal contact lenses dedicated for myopia control.

To measure body balance using computerised dynamic posturography in young adults wearing multifocal contact lenses (MFCL) with high addition powers designed for myopia control. Twenty-four young adults (mean age: 24years) wearing distance-centred soft MFCL (SwissLens Orbis Relax) with two different central zones (3 and 4.5mm), two addition powers (+2D, +4D) and single vision control lenses. Body balance was measured on a moving platform under three viewing conditions: (1) eyes open when fixating on letters at 3m or (2) at 40cm, as well as (3) with the eyes closed. Parameters of body stabilisation were analysed: the rate of body stabilisation (τrelax ), the stabilisation time (Tmax ) and the number of oscillations (Nosc ). The MFCLs did not produce a significant difference in the mean values of the analysed parameters (p>0.05 for τrelax, Tmax, Nosc ). However, a positive correlation was found between pupil size and Nosc and Tmax (p<0.01), suggesting an effect of the +4D add with the 3mm central zone on the posturographic parameters. As was expected, dynamic body stabilisation was better with eyes open versus eyes closed (p<0.005). Distance-centred MFCLs with a medium addition (+2D) do not disturb body stabilisation in young adults. However, high additions (+4D) with a small central zone may affect body balance control in subjects with large pupil size.

Optical aberrations in three different intraocular lens designs of a same platform

PURPOSE:To compare internal optical aberrations between three different intraocular lenses (IOL) of the same Tecnis platform: monofocal ZCB00, multifocal ZMB00, and enlarged depth-of-focus (EDoF) Symfony ZXR00.METHODS:We included in this study 236 eyes of 118 patients who had been bilaterally implanted either with the monofocal, the multifocal, or the EDoF IOL. They were examined with the K1-RW wavefront analyzer (Topcon Medical Systems) 2 months after surgery. Patients with any ocular pathology were excluded from the study. Only high-order aberrations (HOA) of the third and fourth orders of the Zernike polynomials were considered.RESULTS:Forty-three patients (86 eyes) were implanted with the monofocal IOL, 45 patients (90 eyes) with the ZMB00 IOL, and 30 patients (60 eyes) with the EDoF Symfony IOL. Mean age was 62.42 ± 7.38, 63.60 ± 6.01, and 64.74 ± 5.84 years, respectively. Mean axial length was 23.37 ± 1.00, 23.49 ± 1.00, and 23.54 ± 0.73 mm, respectively. For a 6-mm pupil, internal total HOA in the monofocal group was 1.01 ± 1.75 μm; in the bifocal group was 1.35 ± 2.12 μm; and in the Symfony group was 0.72 ± 0.63 μm. No optical aberration differences were found among the three groups (P > 0.05).CONCLUSION:There are no differences regarding internal optical aberrations between these three IOLs when analyzing them with optical aberrometry. Patients’ pupil size should be considered for the selection of the most appropriate IOL to be implanted, because despite a same optical platform, every IOL implies a different increase of HOA with larger pupil sizes.

Comparison of corneal higher-order aberrations after femtosecond lasik and smile for patients with large scotopic pupil size

Comparison of corneal higher-order aberrations after femtosecond lasik and smile for patients with large scotopic pupil size