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1.
Indian J Ophthalmol ; 71(2): 464-466, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36727341

RESUMO

Purpose: Manufacturing a spectacle frame for a facially deformed individual is challenging because of facial asymmetry. One of the solutions is the customization of spectacle frames. Customization of spectacle frames for facially deformed individuals requires a better understanding of the facial anthropometry of deformed faces. This study aimed to analyze the facial anthropometry of deformed faces to understand the range of variability. The results of this study will be used to find customization methods in the future. Methods: We measured and analyzed the 12 facial parameters of individuals with facial deformities using the ImageJ software. Results: The data collected were normally distributed. Paired sample test revealed a statistically significant difference between innercanthus distances (right innercanthus distance [RICD] and left innercanthus distance [LICD]). Correlation analysis showed a positive difference between horizontal and vertical pupillary distance-innercanthus distance (PD-ICD) (0.68, 0.75, and 0.81) and pupillary distance-helix distance (PD-HD) (0.57, 0.68, and 0.59) relations. PD-ICD correlations are stronger compared to the PD-HD relation. Conclusion: Altering the frame center distance and the temple heights are the most important for asymmetric faces. Large population-based data are required to make concrete decisions to design a spectacle frame for asymmetric faces.


Assuntos
Óculos , Face , Humanos , Pupila , Antropometria
3.
Transl Vis Sci Technol ; 12(1): 15, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36622687

RESUMO

Purpose: A scene consisting of a white stimulus on a black background incorporates strong luminance contrast. When both stimulus and background receive different colors, luminance contrast decreases but color contrast increases. Here, we sought to characterize the pattern of stimulus salience across varying trade-offs of color and luminance contrasts by using the pupil light response. Methods: Three experiments were conducted with 17, 16, and 17 healthy adults. For all experiments, a flickering stimulus (2 Hz; alternating color to black) was presented superimposed on a background with a complementary color to the stimulus (i.e., opponency colors in human color perception: blue and yellow for Experiment 1, red and green for Experiment 2, and equiluminant red and green for Experiment 3). Background luminance varied between 0% and 45% to trade off luminance and color contrast with the stimulus. By comparing the locus of the optimal trade-off between color and luminance across different color axes, we explored the generality of the trade-off. Results: The strongest pupil responses were found when a substantial amount of color contrast was present (at the expense of luminance contrast). Pupil response amplitudes increased by 15% to 30% after the addition of color contrast. An optimal pupillary responsiveness was reached at a background luminance setting of 20% to 35% color contrast across several color axes. Conclusions: These findings suggest that a substantial component of pupil light responses incorporates color processing. More sensitive pupil responses and more salient stimulus designs can be achieved by adding subtle levels of color contrast between stimulus and background. Translational Relevance: More robust pupil responses will enhance tests of the visual field with pupil perimetry.


Assuntos
Luz , Pupila , Adulto , Humanos , Pupila/fisiologia , Visão Ocular , Campos Visuais , Percepção de Cores/fisiologia
4.
J. optom. (Internet) ; 16(1)January - March 2023. ilus, tab, graf
Artigo em Inglês | IBECS | ID: ibc-214430

RESUMO

Purpose: The intrinsically photosensitive retinal ganglion cells (ipRGCs) regulate pupil size and circadian rhythms. Stimulation of the ipRGCs using short-wavelength blue light causes a sustained pupil constriction known as the post-illumination pupil response (PIPR). Here we examined the effects of ipRGC stimulation on axial length changes to imposed optical defocus in young adults.Materials and methodsNearly emmetropic young participants were given either myopic (+3 D, n = 16) or hyperopic (-3 D, n = 17) defocus in their right eye for 2 h. Before and after defocus, a series of axial length measurements for up to 180 s were performed in the right eye using the IOL Master following exposure to 5 s red (625 nm, 3.74 × 1014 photons/cm2/s) and blue (470 nm, 3.29 × 1014 photons/cm2/s) stimuli. The pupil measurements were collected from the left eye to track the ipRGC activity. The 6 s and 30 s PIPR, early and late area under the curve (AUC), and time to return to baseline were calculated.ResultsThe PIPR with blue light was significantly stronger after 2 h of hyperopic defocus as indicated by a lower 6 and 30 s PIPR and a larger early and late AUC (all p<0.05). Short-wavelength ipRGC stimulation also significantly exaggerated the ocular response to hyperopic defocus, causing a significantly greater increase in axial length than that resulting from the hyperopic defocus alone (p = 0.017). Neither wavelength had any effect on axial length with myopic defocus.ConclusionsThese findings suggest an interaction between myopiagenic hyperopic defocus and ipRGC signaling. (AU)


Assuntos
Humanos , Adulto Jovem , Hiperopia , Luz , Miopia/terapia , Estimulação Luminosa , Pupila/fisiologia , Células Ganglionares da Retina
5.
Agri ; 35(1): 22-27, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36625194

RESUMO

OBJECTIVES: Pain is a subjective experience. Besides, sensory, affective and behavioral responses, and autonomic response are part of pain response to noxious stimuli. Evaluation of pupil diameter by pupillometry has been used as an alternative method for pain assessment. In algologic procedures like interventional headache management have not been addressed in the literature. Herein, we investigated changes in pupil diameter during interventional headache management as an objective method for pain assessment. METHODS: Demographic data of the patients were collected before the bilateral major occipital nerve blockage (MONB) procedure. Numeric rating score (NRS) and pupil diameter measurements by pupillometer were recorded before MONB. Standard MONB procedure was applied to all patients. Pain assessment and pupillary diameter measurements were obtained after nerve blockage. RESULTS: Twenty-eight patients were included in this study. Mean age was 41.03+-12.63 years. There is no difference between the hemodynamic parameters before and after the procedure. Post-procedure NRS and pupil diameter values were significantly lower than pre-procedure values. There was a positive correlation between changes in NRS scores and changes in the right and left pupil diameters. CONCLUSION: There was a significant correlation between NRS score and pupil diameter in patients who underwent MONB. Monitoring of pupil diameter can be used for pain assessment during headache treatment. Evaluation of pupil diameter is a new approach in pain palliation. Future research is needed to study the effect of other parameters, that is, gender, age, origin of pain, acute, and chronic pain on pupil diameter and to evaluate its application in different algological procedures.


Assuntos
Dor , Pupila , Humanos , Adulto , Pessoa de Meia-Idade , Pupila/fisiologia , Medição da Dor/métodos , Cefaleia/diagnóstico
6.
Indian J Ophthalmol ; 71(1): 57-61, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36588207

RESUMO

Purpose: To study the effect of pupil dilation on a biometric iris recognition (BIR) system for personal authentication and identification. Methods: A prospective, non-randomized, single-center cohort study was conducted on patients who reported for a routine eye check-up from November 2017 to November 2019 (2 years). An iris scanning device "IRITECH-MK2120U" was used to initially enroll the undilated eyes. Baseline scans were taken after matching with the enrolled database. All eyes were topically dilated and matched again with the enrolled database. The Hamming distance (a measure of disagreement between two iris codes) and recognition status were recorded from the device output, and eyes were evaluated by slit-lamp ophthalmoscopy with special emphasis on pupil shape, size, and texture. Results: All 321 enrolled eyes matched after topical dilation. The pupil size had a significant effect on Hamming distance with a P value <0.05. There were no false matches. A correct recognition rate of 100% was obtained after dilation. No loss of iris texture or pupil shape was observed after dilation. Conclusion: A BIR system is a reliable method for identification and personal authentication after pupil dilation. Topically dilated pupils are not a cause for non-recognition of iris scans.


Assuntos
Biometria , Pupila , Humanos , Estudos de Coortes , Estudos Prospectivos , Biometria/métodos , Iris
7.
Transl Vis Sci Technol ; 12(1): 9, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36607622

RESUMO

Purpose: To present FIAT, a novel optical instrument and analysis package that is designed to elicit and optically record accommodation in human eyes. Methods: FIAT employs a Shack-Hartmann wavefront sensor and a retro-illumination pupil camera that records from a single eye at video rates. It is effective at eliciting accommodation by offering the subject a full-field binocular view of an alternating distant target and a near-eye display. FIAT analysis software computes wave aberrations for each video frame over full- or subpupil sizes and computes accommodative dynamics and accommodative range. Results: The system is validated by showing accurate refraction measurements in model eyes and human eyes with trial lenses. Robust accommodative responses are shown for young eyes, and a lack of accommodative response is shown for a known presbyopes. Accommodative stimulus-response curves from five phakic subjects over a range of ages show expected results. Results from two individuals with monofocal intraocular lenses are shown. Conclusions: FIAT is an effective instrument for making accurate, objective measures of accommodation in phakic and pseudophakic eyes. Translational Relevance: We present a device that can play an important role in the development and testing of accommodating intraocular lenses.


Assuntos
Lentes Intraoculares , Pseudofacia , Humanos , Acomodação Ocular , Pupila/fisiologia
8.
J Cataract Refract Surg ; 49(1): 21-28, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36573762

RESUMO

PURPOSE: To assess the repeatability and agreement of Cartesian coordinates and the length of apparent chord mu and pupil diameter measurements during static (Galilei G4) and dynamic (Topolyzer Vario) evaluations. SETTING: IOBA-Eye Institute, Valladolid, Spain. DESIGN: Case series. METHODS: 3 consecutive measurements per scenario (Galilei G4 and Topolyzer Vario under low mesopic and photopic conditions) were performed by the same clinician. The intrasession repeatability was assessed using the within-subject SD (Sw), the precision, the coefficient of variation, and the intraclass correlation coefficient (ICC). The agreement was analyzed using repeated-measures analysis of variance and the Bland-Altman method. RESULTS: Thirty-seven healthy participants were recruited. The Sw values for chord mu parameters and pupil diameter ranged from 0.01 to 0.03 and 0.08 to 0.21, respectively. The ICC was ≥0.89 for all parameters. Galilei G4 and Topolyzer Vario under low mesopic and photopic conditions provided significantly different measures of apparent chord mu length (0.23 ± 0.11 mm, 0.30 ± 0.10 mm, and 0.25 ± 0.11 mm, respectively, P ≤ .02), X-coordinate (-0.18 ± 0.12 mm, -0.27 ± 0.11 mm, and -0.21 ± 0.12 mm, respectively, P < .001), and pupil diameter (3.38 ± 0.50 mm, 6.29 ± 0.60 mm, and 3.04 ± 0.41 mm, respectively, P < .001). Y-coordinate values obtained by Galilei G4 and Topolyzer Vario under low mesopic conditions were significantly different (0.06 ± 0.13 mm vs 0.03 ± 0.11 mm, respectively, P = .02), in contrast to Galilei G4 and Topolyzer Vario under photopic conditions (0.05 ± 0.13 mm, P = .82) and both illumination conditions of Topolyzer Vario (P ≥ .23). CONCLUSIONS: Galilei G4 and Topolyzer Vario provide consistent measurements of apparent chord mu Cartesian coordinates and length, as well as pupil diameter; however, the measurements are not interchangeable. Ophthalmic surgeons should consider these findings when planning customized intraocular lens implantation and refractive surgery procedures.


Assuntos
Visão de Cores , Procedimentos Cirúrgicos Refrativos , Humanos , Reprodutibilidade dos Testes , Voluntários Saudáveis , Iluminação , Pupila
9.
Int Ophthalmol ; 42(2): 385-391, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34613562

RESUMO

AIM: To compare pupillary responses in patients with Coronavirus disease-2019 (COVID-19) during active infection and at 3rd months post-infection. METHODS: This study included 58 COVID-19 cases (mean age 47.23 ± 1.1 years). The scotopic, mesopic and photopic diameters were noted. Pupil diameters were noted at the 0, 1st, 2nd, 4th, 6th, 8th, and 10th seconds in reflex pupil dilation after the termination of a light. The average dilation speed was calculated at the 1st, 2nd, 4th, 6th, 8th, and 10th seconds. Pupil responses measured during COVID-19 infection and 3 months later were compared. RESULTS: The mean scotopic and mesopic pupil diameter value of during COVID-19 infection was found lower than the 3rd month post-infection. (p = 0.001, p = 0.023; respectively). No statistically significant difference was found in the mean photopic pupil diameter and the mean pupil diameter at 0 s between measurements (p > 0.05, p = 0.734; respectively). The mean pupil diameter was significantly lower during COVID-19 infection at the 1st, 2nd, 4th, 6th, 8th and 10th seconds (p < 0.01, for each). The average dilation speed measurements at every second measured were lower in during COVID-19 infection than the 3rd months later (p = 0.001; p < 0.01 for each). CONCLUSIONS: Pupil responses were found significantly different in COVID-19 cases when compared with the measurements taken three months later.


Assuntos
COVID-19 , Visão de Cores , Humanos , Pessoa de Meia-Idade , Pupila/fisiologia , SARS-CoV-2
10.
PLoS One ; 17(12): e0278506, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36459511

RESUMO

There is an increasing interest in the field of audiology and speech communication to measure the effort that it takes to listen in noisy environments, with obvious implications for populations suffering from hearing loss. Pupillometry offers one avenue to make progress in this enterprise but important methodological questions remain to be addressed before such tools can serve practical applications. Typically, cocktail-party situations may occur in less-than-ideal lighting conditions, e.g. a pub or a restaurant, and it is unclear how robust pupil dynamics are to luminance changes. In this study, we first used a well-known paradigm where sentences were presented at different signal-to-noise ratios (SNR), all conducive of good intelligibility. This enabled us to replicate findings, e.g. a larger and later peak pupil dilation (PPD) at adverse SNR, or when the sentences were misunderstood, and to investigate the dependency of the PPD on sentence duration. A second experiment reiterated two of the SNR levels, 0 and +14 dB, but measured at 0, 75, and 220 lux. The results showed that the impact of luminance on the SNR effect was non-monotonic (sub-optimal in darkness or in bright light), and as such, there is no trivial way to derive pupillary metrics that are robust to differences in background light, posing considerable constraints for applications of pupillometry in daily life. Our findings raise an under-examined but crucial issue when designing and understanding listening effort studies using pupillometry, and offer important insights to future clinical application of pupillometry across sites.


Assuntos
Pupila , Fala , Cognição , Percepção Auditiva , Razão Sinal-Ruído
11.
Indian J Ophthalmol ; 70(12): 4312-4318, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36453336

RESUMO

Purpose: To study the use of sulcus placement of a 3-piece intraocular lens (IOL) with optic capture in patients with exfoliation with zonular weakness. Methods: Data on all exfoliation patients who had direct or indirect evidence of zonular weakness and had a 3-piece IOL implanted in the sulcus with optic capture over a 5-year period between January 2017 and January 2022 were included in this retrospective case series. Results: The study comprised of 35 eyes of 35 patients. The mean age at surgery of the 20 male and 13 female patients was 75.21 years ± 5.74 (standard deviation (SD)). The mean pupillary diameter was 5.77 ± 2.23 mm (range: 10 to 3 mm). A capsular tension ring (CTR) was used in 17 cases and iris hooks as a pupil-expanding device were used in 15 cases. No patients had an increase in inflammation after surgery and there were no late subluxation or dislocation of "in the bag" posterior chamber IOL or major complications. There was a significant improvement in visual acuity. Conclusion: The sulcus placement of 3-piece IOL with optic capture is the ideal technique in patients with clinical or intraoperative evidence of mild to moderate zonular weakness. It may also be more appropriate in relatively younger patients (in the fifties or sixties) with exfoliation with no overt zonulopathy to prevent late subluxation or dislocation of "in the bag" IOL.


Assuntos
Lentes Intraoculares , Feminino , Masculino , Humanos , Estudos Retrospectivos , Olho Artificial , Pupila , Iris
12.
Indian J Ophthalmol ; 70(12): 4325-4330, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36453339

RESUMO

Purpose: To study and describe clinical characteristics of congenital and developmental cataract at a tertiary eye care facility. Methods: In this retrospective study, 942 children (1311 eyes) presenting with congenital/developmental cataract over a 10-year study period were included. Gender, age at surgery, main presenting complaint, morphologic type of cataract, laterality, family history, and associated findings were recorded. Results: The overall proportion of boys and girls undergoing cataract surgery was approximately equal (P = 0.110). However, in the cases of bilateral cataract, the proportion of boys was larger than girls (P = 0.028). More than half (62.3%) of the patients underwent surgery at the age of >3 years. The main presenting complaint was white pupils, accounting for 48.1% of cases. Total cataract was the most common morphologic type in all age groups. In total, 133 children out of 942 (14.1%) had a positive family history of congenital/developmental cataract. Strabismus and nystagmus were seen in 27.2% and 19.3% of the eyes, respectively. Additional ocular dysmorphology was found in 97 (10.3%) of patients. Coexisting systemic disease was found in 149 (15.8%) cases. Among syndrome-associated cataracts, Down syndrome accounted for the majority of cases. Conclusion: High prevalence of total cataracts as well as frequent association with strabismus and nystagmus are likely to be the consequences of delayed presentation.


Assuntos
Catarata , Nistagmo Patológico , Estrabismo , Masculino , Criança , Feminino , Humanos , Pré-Escolar , Cazaquistão , Estudos Retrospectivos , Catarata/epidemiologia , Pupila
13.
Sensors (Basel) ; 22(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36502099

RESUMO

Eye-gaze direction-tracking technology is used in fields such as medicine, education, engineering, and gaming. Stability, accuracy, and precision of eye-gaze direction-tracking are demanded with simultaneous upgrades in response speed. In this study, a method is proposed to improve the speed with decreases in the system load and precision in the human pupil orbit model (HPOM) estimation method. The new method was proposed based on the phenomenon that the minor axis of the elliptical-deformed pupil always pointed toward the rotational center presented in various eye-gaze direction detection studies and HPOM estimation methods. Simulation experimental results confirmed that the speed was improved by at least 74 times by consuming less than 7 ms compared to the HPOM estimation. The accuracy of the eye's ocular rotational center point showed a maximum error of approximately 0.2 pixels on the x-axis and approximately 8 pixels on the y-axis. The precision of the proposed method was 0.0 pixels when the number of estimation samples (ES) was 7 or less, which showed results consistent with those of the HPOM estimation studies. However, the proposed method was judged to work conservatively against the allowable angle error (AAE), considering that the experiment was conducted under the worst conditions and the cost used to estimate the final model. Therefore, the proposed method could estimate HPOM with high accuracy and precision through AAE adjustment according to system performance and the usage environment.


Assuntos
Fixação Ocular , Pupila , Humanos , Pupila/fisiologia , Cabeça , Simulação por Computador
14.
Sci Rep ; 12(1): 22098, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36543845

RESUMO

In this study, we examined the relationship between physiological encoding of surprise and the learning of anticipatory eye movements. Active inference portrays perception and action as interconnected inference processes, driven by the imperative to minimise the surprise of sensory observations. To examine this characterisation of oculomotor learning during a hand-eye coordination task, we tested whether anticipatory eye movements were updated in accordance with Bayesian principles and whether trial-by-trial learning rates tracked pupil dilation as a marker of 'surprise'. Forty-four participants completed an interception task in immersive virtual reality that required them to hit bouncing balls that had either expected or unexpected bounce profiles. We recorded anticipatory eye movements known to index participants' beliefs about likely ball bounce trajectories. By fitting a hierarchical Bayesian inference model to the trial-wise trajectories of these predictive eye movements, we were able to estimate each individual's expectations about bounce trajectories, rates of belief updating, and precision-weighted prediction errors. We found that the task-evoked pupil response tracked prediction errors and learning rates but not beliefs about ball bounciness or environmental volatility. These findings are partially consistent with active inference accounts and shed light on how encoding of surprise may shape the control of action.


Assuntos
Pupila , Realidade Virtual , Humanos , Teorema de Bayes , Aprendizagem , Movimentos Oculares , Desempenho Psicomotor
15.
Sensors (Basel) ; 22(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36560280

RESUMO

Iris localization in non-cooperative environments is challenging and essential for accurate iris recognition. Motivated by the traditional iris-localization algorithm and the robustness of the YOLO model, we propose a novel iris-localization algorithm. First, we design a novel iris detector with a modified you only look once v4 (YOLO v4) model. We can approximate the position of the pupil center. Then, we use a modified integro-differential operator to precisely locate the iris inner and outer boundaries. Experiment results show that iris-detection accuracy can reach 99.83% with this modified YOLO v4 model, which is higher than that of a traditional YOLO v4 model. The accuracy in locating the inner and outer boundary of the iris without glasses can reach 97.72% at a short distance and 98.32% at a long distance. The locating accuracy with glasses can obtained at 93.91% and 84%, respectively. It is much higher than the traditional Daugman's algorithm. Extensive experiments conducted on multiple datasets demonstrate the effectiveness and robustness of our method for iris localization in non-cooperative environments.


Assuntos
Algoritmos , Iris , Pupila
16.
PLoS Comput Biol ; 18(12): e1010785, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36548401

RESUMO

Supplementation with the catecholamine precursor L-Tyrosine might enhance cognitive performance, but overall findings are mixed. Here, we investigate the effect of a single dose of tyrosine (2g) vs. placebo on two catecholamine-dependent trans-diagnostic traits: model-based control during reinforcement learning (2-step task) and temporal discounting, using a double-blind, placebo-controlled, within-subject design (n = 28 healthy male participants). We leveraged drift diffusion models in a hierarchical Bayesian framework to jointly model participants' choices and response times (RTS) in both tasks. Furthermore, comprehensive autonomic monitoring (heart rate, heart rate variability, pupillometry, spontaneous eye blink rate) was performed both pre- and post-supplementation, to explore potential physiological effects of supplementation. Across tasks, tyrosine consistently reduced participants' RTs without deteriorating task-performance. Diffusion modeling linked this effect to attenuated decision-thresholds in both tasks and further revealed increased model-based control (2-step task) and (if anything) attenuated temporal discounting. On the physiological level, participants' pupil dilation was predictive of the individual degree of temporal discounting. Tyrosine supplementation reduced physiological arousal as revealed by increases in pupil dilation variability and reductions in heart rate. Supplementation-related changes in physiological arousal predicted individual changes in temporal discounting. Our findings provide first evidence that tyrosine supplementation might impact psychophysiological parameters, and suggest that modeling approaches based on sequential sampling models can yield novel insights into latent cognitive processes modulated by amino-acid supplementation.


Assuntos
Desvalorização pelo Atraso , Humanos , Masculino , Teorema de Bayes , Tirosina/farmacologia , Reforço Psicológico , Nível de Alerta , Pupila/fisiologia
17.
J Neural Eng ; 19(6)2022 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-36583387

RESUMO

Objective:recently, pupil oscillations synchronized with steady visual stimuli were used as input for an interface. The proposed system, inspired by a brain-computer interface based on steady-state visual evoked potentials, does not require contact with the participant. However, the pupil oscillation mechanism limits the stimulus frequency to 2.5 Hz or less, making it hard to enhance the information transfer rate (ITR).Approach:here, we compared multiple conditions for stimulation to increase the ITR of the pupil vibration-based interface, which were called monocular-single, monocular-superposed, and binocular-independent conditions. The binocular-independent condition stimulates each eye at different frequencies respectively and mixes them by using the visual stereoscopic perception of users. The monocular-superposed condition stimulates both eyes by a mixed signal of two different frequencies. We selected the shape of the stimulation signal, evaluated the amount of spectral leakage in the monocular-superposed and binocular-independent conditions, and compared the power spectrum density at the stimulation frequency. Moreover, 5, 10, and 15 patterns of stimuli were classified in each condition.Main results:a square wave, which causes an efficient pupil response, was used as the stimulus. Spectral leakage at the beat frequency was higher in the monocular-superposed condition than in the binocular-independent one. The power spectral density of stimulus frequencies was greatest in the monocular-single condition. Finally, we could classify the 15-stimulus pattern, with ITRs of 14.4 (binocular-independent, using five frequencies), 14.5 (monocular-superimposed, using five frequencies), and 23.7 bits min-1(monocular-single, using 15 frequencies). There were no significant differences for the binocular-independent and monocular-superposed conditions.Significance:this paper shows a way to increase the number of stimuli that can be simultaneously displayed without decreasing ITR, even when only a small number of frequencies are available. This could lead to the provision of an interface based on pupil oscillation to a wider range of users.


Assuntos
Pupila , Visão Binocular , Humanos , Pupila/fisiologia , Visão Binocular/fisiologia , Potenciais Evocados Visuais , Visão Monocular/fisiologia , Reflexo , Estimulação Luminosa
18.
Invest Ophthalmol Vis Sci ; 63(12): 17, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36374515

RESUMO

Purpose: We investigated decline in the visual function of eyes with retrodots (RDs)-a subtype of cataract. Method: This study included 57 eyes with RD opacity only (mean age 72.3 ± 5.2 years) and 34 eyes with transparent lenses (mean age 71.4 ± 3.7 years). A physician diagnosed lens opacity. Using the Kanazawa Medical University Classification and Grading System, the eyes were classified into the RD-1 (37 eyes, RDs <25% of the 3-mm pupil area) and RD-2 (20 eyes, RDs ≥25% of the 3-mm pupil area) groups. Corrected distance visual acuity, contrast visual acuity, ocular refractive power, lens power, straylight, and backward light-scattering intensity and their relationship with visual function decline and optical characteristics of the eyeball were evaluated. Results: Corrected distance visual acuity was significantly lower in the RD eyes than in controls. Contrast visual acuity decreased significantly in the RD-2 eyes in all environments and in the RD-1 eyes in the evening (EVE) and EVE + glare. Straylight was significantly higher in the RD-2 eyes than in the controls and RD-1 eyes but not different between the RD-1 eyes and controls. The RD-2 eyes were significantly more myopic than the controls and RD-1 eyes. Conclusion: When the opacity of RD eyes is ≥25%, the visual acuity and contrast visual acuity decrease and straylight increases. Furthermore, myopia occurs as the refractive power of the lens increases. Moreover, visual function decline may be due to an increase in the straylight value, which is necessary for determining surgical indications.


Assuntos
Catarata , Miopia , Humanos , Idoso , Espalhamento de Radiação , Ofuscação , Acuidade Visual , Pupila
19.
Transl Vis Sci Technol ; 11(11): 6, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36342706

RESUMO

Purpose: To analyze natural variability in pupillary contractility with dynamic volume-rendered optical coherence tomography (OCT) pupillometry regarding iris color, age, and sex in healthy Caucasian participants. Methods: The intrapupillary spaces (IPSs) derived from anterior segment swept-source OCT of 71 healthy eyes were retrospectively analyzed. Baseline scotopic and photopic volumes and the functional parameters of pupillary ejection fraction (PEF), three-dimensional (3D) contractility, and relative light response (RLR) were measured on the swept-source OCT volumes. The effect on these parameters of iris color (brown, green, and blue), age, and sex was assessed. Results: More pigmented irises were more contractile than less pigmented irises. Iris color significantly affected scotopic baseline IPSs (brown, 10.39 ± 4.86 mm3; green, 9.68 ± 3.31 mm3; blue, 6.75 ± 4.27 mm3; P = 0.018), PEF (brown, 90.8% ± 2.7%; green, 89.1% ± 2.5%; blue, 85.0% ± 9.3%; P = 0.010), 3D contractility (brown, 9.52 ± 4.59 mm3; green, 8.66 ± 3.07 mm3; blue, 6.44 ± 4.87 mm3; P = 0.016), and RLR (brown, 11.90 ± 4.03; green, 9.75 ± 2.73; blue, 8.52 ± 3.88; P = 0.026). Absolute scotopic volume (P = 0.022) and 3D contractility (P = 0.024) decreased with age. Sex showed no correlations. Conclusions: The natural variability of pupillary contractility can be analyzed with dynamic OCT pupillometry. Iris color and age can impact pupillary response with this method. Translational Relevance: Iris contractility parameters can be measured using a commercially available OCT system, allowing for quantification of the aqueous humor volume inside the pupil.


Assuntos
Visão de Cores , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Estudos Retrospectivos , Iris/diagnóstico por imagem , Pupila/fisiologia
20.
Nat Commun ; 13(1): 6760, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36351937

RESUMO

The human light modulation response allows humans to perceive objects clearly by receiving the appropriate amount of light from the environment. This paper proposes a biomimetic ocular prosthesis system that mimics the human light modulation response capable of pupil and corneal reflections. First, photoinduced synaptic properties of the quantum dot embedded photonic synapse and its biosimilar signal transmission is confirmed. Subsequently, the pupillary light reflex is emulated by incorporating the quantum dot embedded photonic synapse, electrochromic device, and CMOS components. Moreover, a solenoid-based eyelid is connected to the pupillary light reflex system to emulate the corneal reflex. The proposed ocular prosthesis system represents a platform for biomimetic prosthesis that can accommodate an appropriate amount of stimulus by self-regulating the intensity of external stimuli.


Assuntos
Pupila , Reflexo Pupilar , Humanos , Pupila/fisiologia , Reflexo Pupilar/fisiologia , Olho Artificial , Biomimética , Sistema Nervoso Autônomo
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