scholarly journals Factors Influencing Pseudo-Accommodation—The Difference between Subjectively Reported Range of Clear Focus and Objectively Measured Accommodation Range

Vision ◽  
2019 ◽  
Vol 3 (3) ◽  
pp. 34
Author(s):  
Dhallu ◽  
Sheppard ◽  
Drew ◽  
Mihashi ◽  
Zapata-Díaz ◽  
...  
Keyword(s):  
Pupil Size ◽  
Pupil Diameter ◽  
Spherical Aberration ◽  
Crystalline Lens ◽  
Clear Vision ◽  
Ocular Aberrations ◽  
Defocus Curve ◽  
Neural Factors ◽  
The Difference ◽  
Objectively Measured

The key determinants of the range of clear focus in pre-presbyopes and their relative contributions to the difference between subjective range of focus and objective accommodation assessments have not been previously quantified. Fifty participants (aged 33.0 ± 6.4 years) underwent simultaneous monocular subjective (visual acuity measured with an electronic test-chart) and objective (dynamic accommodation measured with an Aston open-field aberrometer) defocus curve testing for lenses between +2.00 to -10.00 DS in +0.50 DS steps in a randomized order. Pupil diameter and ocular aberrations (converted to visual metrics normalized for pupil size) at each level of blur were measured. The difference between objective range over which the power of the crystalline lens changes and the subjective range of clear focus was quantified and the results modelled using pupil size, refractive error, tolerance to blur, and ocular aberrations. The subjective range of clear focus was principally accounted for by age (46.4%) and pupil size (19.3%). The objectively assessed accommodative range was also principally accounted for by age (27.6%) and pupil size (15.4%). Over one-quarter (26.0%) of the difference between objective accommodation and subjective range of clear focus was accounted for by age (14.0%) and spherical aberration at maximum accommodation (12.0%). There was no significant change in the objective accommodative response (F=1.426, p=0.229) or pupil size (F=0.799, p=0.554) of participants for levels of defocus above their amplitude of accommodation. Pre-presbyopes benefit from an increased subjective range of clear vision beyond their objective accommodation due in part to neural factors, resulting in a measured depth-of-focus of, on average, 1.0D.

scholarly journals Relationship between facial attractiveness and pupil diameter in young adults

Psico ◽  
2019 ◽  
Vol 50 (2) ◽  
pp. 30033
Author(s):  
Silvana Queiroga da Costa Carvalho ◽  
Michael Jackson Oliveira De Andrade ◽  
Natanael Antonio Dos Santos
Keyword(s):  
Young Adults ◽  
Phase I ◽  
Pupil Size ◽  
Pupil Diameter ◽  
Facial Attractiveness ◽  
Human Face ◽  
Significant Difference ◽  
The Difference ◽  
Post Hoc ◽  
Step Study

The objective of this study was to investigate whether there is a relationship between pupil diameter and facial attractiveness. Participated in the study 60 young adults (30 men and 30 women) between 18 and 26 years of age (M = 20.65, SD = 2.20). Ten different unfamiliar neutral faces (five men and five women) were used as stimuli. The pupil diameter of each face was manipulated with pupil diameters of 2, 3, 4, 5 and 6 mm (10 faces x 5 pupil diameters = 50stimuli). A two-step study was carried out with the same sample and the same sets of faces, seeking to understand the difference of responses between subjects of both sexes. In phase I, result indicated a significant difference in relation to the pupil diameter factor for both the men (ꭓ² = 21.93, p < .05) and the women (ꭓ² = 44.73, p < .05). In phase II, the results indicated significant differences in relation to the pupil size [F (1, 234) = 19.06, p < 0.05]. The post-hoc Tukey HSD test showed that both the men and the women differently judged the faces with a pupil diameter of 2 mm in relation to the faces with pupil diameters of 3, 4, 5 and 6 mm (p < .05). Also, a significant difference between the diameter of 5 mm in relation to the diameter of 3 mm (p < .05). In general, the results indicate that the pupil diameter is a structural component of the human face that plays an important role in the process of judging facial attractiveness.***Relação entre a atratividade facial e diâmetro pupilar em adultos jovens***O objetivo deste estudo foi investigar a relação entre o diâmetro da pupila e a atratividade facial. Participaram da pesquisa 60 jovens com idade entre 18 e 26 anos. Foram utilizadas dez faces de adultos jovens, manipulou-se o diâmetro de cada pupila com variações de 2, 3, 4, 5 e 6 mm. Realizou-se um estudo em duas etapas: na fase I, o resultado indicou diferença significativa para o fator de diâmetro pupilar tanto para homens quanto para mulheres (p < 0,05). Na fase II, os resultados indicaram diferenças significativas em relação ao tamanho da pupila (p < 0,05). O teste post-hoc Tukey mostrou que tanto os homens quanto as mulheres avaliaram diferentemente as faces com diâmetro pupilar de 2 mm (p < 0,05). Em geral, os resultados indicam que o diâmetro da pupila é um componente da face humana que desempenha um importante função no processo de julgamento da atratividade facial.

scholarly journals Acute Effect of Cigarette Smoking on Pupil Size and Ocular Aberrations: A Pre- and Postsmoking Study

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Uzeyir Erdem ◽  
Fatih C. Gundogan ◽  
Umut Aslı Dinc ◽  
Umit Yolcu ◽  
Abdullah Ilhan ◽  
...  
Keyword(s):  
Cigarette Smoking ◽  
Pupil Size ◽  
Spherical Aberration ◽  
Acute Effect ◽  
Optical Path Difference ◽  
Higher Order ◽  
Scanning System ◽  
Wavefront Aberration ◽  
Ocular Aberrations ◽  
Higher Order Aberration

Aim.To evaluate the acute effects of cigarette smoking on photopic and mesopic pupil sizes and wavefront aberrations.Methods.Cigarette smoker volunteers were recruited in the study. Photopic and mesopic pupil sizes and total ocular aberrations were measured before smoking and immediately after smoking. All volunteers were asked to smoke a single cigarette containing 1.0 mg nicotine. Pupil sizes and total ocular aberrations were assessed by optical path difference scanning system (OPD-Scan II ARK-10000, NIDEK). Only the right eyes were considered for statistical analysis. The changes of pupil size and total ocular aberrations after smoking were tested for significance by Wilcoxon signed ranks test.Results.Mean photopic pupil size decreased from 3.52 ± 0.73 mm to 3.29 ± 0.58 mm(P=0.001)after smoking. Mean mesopic pupil size was also decreased from 6.42 ± 0.75 mm to 6.14 ± 0.75 mm after smoking(P=0.001). There was a decrease in all the measured components of aberrations (total wavefront aberration, higher-order aberration, total coma, total trefoil, total tetrafoil, total spherical aberration and total higher-order aberration) after smoking; however the differences were insignificant for all(P>0.05).Conclusion.Our results indicate that pupil constricts after smoking. On the other hand, smoking does not alter ocular aberrations.

Clinical evaluation of the repeatability of ocular aberrometry obtained with a new pyramid wavefront sensor

2018 ◽  
Vol 29 (6) ◽  
pp. 585-592 ◽  
Author(s):  
Ana B Plaza-Puche ◽  
Liberdade C Salerno ◽  
Francesco Versaci ◽  
Daniel Romero ◽  
Jorge L Alio
Keyword(s):  
Standard Deviation ◽  
Correlation Coefficient ◽  
Intraclass Correlation Coefficient ◽  
Pupil Size ◽  
Pupil Diameter ◽  
Intraclass Correlation ◽  
Wavefront Sensor ◽  
Mean Square ◽  
The Subject ◽  
Healthy Eyes

Purpose:To evaluate the intrasubject repeatability of the ocular aberrometry obtained with a new ocular pyramidal aberrometer technology in a sample of normal eyes.Methods:A total of 53 healthy eyes of 53 subjects with ages ranging from 18 to 45 years were included in this study. In all cases, three consecutive acquisitions were obtained. Intrasubject repeatability of the measurements with a pyramidal aberrometer was calculated. Intrasubject repeatability for 4.0- and 6.0-mm pupils was evaluated within the subject standard deviation (Sw) and intraclass correlation coefficient.Results:Low values of the Swand intraclass correlation coefficient outcomes close to 1 were observed for the sphere and cylinder at 3.0-mm pupil size. Most low Swand intraclass correlation coefficient values close to 1 were observed for total, low-order aberrations and higher-order aberrations root mean square and for each Zernike coefficient analysis (intraclass correlation coefficient ⩾0.798) at 4.0-mm pupil size, with more limited outcomes for the aberrometric coefficient of Z(4, 4) with an intraclass correlation coefficient of 0.683. For a 6.0 mm pupil diameter, low Swand intraclass correlation coefficient values close to 1 were observed for all aberrometric parameters or Zernike coefficients analyzed (intraclass correlation coefficient ⩾0.850).Conclusion:The new pyramidal aberrometer Osiris provides repeatable and consistent measurements of ocular aberrometry measurements in normal eyes.

scholarly journals Effect of Spherical Aberration on the Optical Quality after Implantation of Two Different Aspherical Intraocular Lenses

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Michael Lasta ◽  
Kata Miháltz ◽  
Illés Kovács ◽  
Pia Veronika Vécsei-Marlovits
Keyword(s):  
Contrast Sensitivity ◽  
Pupil Size ◽  
Spherical Aberration ◽  
Optical Quality ◽  
Intraocular Lenses ◽  
Strehl Ratio ◽  
Minimum Diameter ◽  
Link Type ◽  
Medical Optics ◽  
Aspherical Iol

Purpose. To compare the effect of spherical aberration on optical quality in eyes with two different aspherical intraocular lenses. Methods. 120 eyes of 60 patients underwent phacoemulsification. In patients’ eyes, an aberration-free IOL (Aspira-aA; Human Optics) or an aberration-correcting aspherical IOL (Tecnis ZCB00; Abott Medical Optics) was randomly implanted. After surgery, contrast sensitivity and wavefront measurements as well as tilt and decentration measurements were performed. Results. Contrast sensitivity was significantly higher in eyes with Aspira lens under mesopic conditions with 12 cycles per degree (CPD) and under photopic conditions with 18 CPD (p=0.02). Wavefront measurements showed a higher total spherical aberration with a minimal pupil size of 4 mm in the Aspira group (0.05 ± 0.03) than in the Tecnis group (0.03 ± 0.02) (p=0.001). Strehl ratio was higher in eyes with Tecnis (0.28 ± 0.17) with a minimal pupil size larger than 5 mm than that with Aspira (0.16 ± 0.14) (p=0.04). In pupils with a minimum diameter of 4 mm spherical aberration had a significant effect on Strehl ratio, but not in pupils with a diameter less than 4 mm. Conclusions. Optical quality was better in eyes with the aberration-correcting Tecnis IOL when pupils were large. In contrast, this could not be shown in eyes with pupils under 4 mm or larger. This trial is registered with Clinicaltrials.gov NCT03224728.

Changes in pupil diameter entrained by cortically initiated changes in attention

2012 ◽  
Vol 29 (2) ◽  
pp. 131-142 ◽  
Author(s):  
LORI B. DANIELS ◽  
DAVID F. NICHOLS ◽  
MATHEW S. SEIFERT ◽  
HOWARD S. HOCK
Keyword(s):  
Cognitive Processes ◽  
Pupil Diameter ◽  
Spherical Aberration ◽  
Receptive Fields ◽  
Relative Sensitivity ◽  
Focused Attention ◽  
Intentional Control ◽  
Subcortical Nuclei ◽  
Behavioral Evidence ◽  
Near Reflex

AbstractThe diameter of the pupil is affected by changes in ambient illumination, color, spatial structure, movement, and mental effort. It has now been found that pupil diameter can be affected by cognitive processes. That is, it can be entrained by alternations between broadly spread and narrowly focused attention that are cued exogenously (attention is “summoned” by the cue) or endogenously (attention changes under the perceiver’s intentional control). Pupil diameter also is affected by post-eye-blink constrictions that occur most often when attention is narrowed, and possibly by changes evoked by the near reflex, although changes in attention state parsimoniously account for the entirety of the results. Changes in pupil diameter produce differences in spherical aberration that alternately blur (when the pupil dilates) and sharpen the retinal image (when the pupil constricts), affecting the relative sensitivity of large receptive fields that mediate broadly spread attention compared with smaller receptive fields that mediate more narrowly focused attention. Results for endogenously cued, intentional changes in attentional spread provide definitive behavioral evidence for cortical feedback to subcortical nuclei that control pupil diameter, either directly or through pupil-constricting eye blinks. Analyses of convergent and divergent changes in eye position indicate that the near reflex was activated long after the initiation of relatively gradual attentionally cued changes in pupil diameter, and further, that when it occurs, the near reflex facilitates ongoing changes in pupil diameter.

Prospective analysis of visual function changes in patients with dermatochalasis after upper eyelid blepharoplasty

2019 ◽  
Vol 30 (5) ◽  
pp. 978-984
Author(s):  
Meryem Altin Ekin ◽  
Seyda Karadeniz Ugurlu
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Visual Function ◽  
Spherical Aberration ◽  
Higher Order ◽  
Rank Test ◽  
Higher Order Aberrations ◽  
Upper Eyelid ◽  
Spatial Frequencies ◽  
The Difference

Objective: To evaluate the changes of visual acuity, contrast sensitivity, astigmatism, and higher order aberrations after blepharoplasty in patients with dermatochalasis. Methods: Two hundred six eyelids of 103 patients with dermatochalasis were prospectively studied. Visual acuity, contrast sensitivity, corneal topography, astigmatism degree, and higher order aberrations were examined and recorded before and at 1 month after upper eyelid blepharoplasty. Change in contrast sensitivity and astigmatism values were determined according to margin reflex distance of patients, which were classified into three following groups: <2 mm, 2–3 mm, and ⩾ 4 mm. A Wilcoxon signed rank test was performed to compare the difference. Results: No significant differences were observed for visual acuity (p = 0.157). The contrast sensitivity of patients significantly increased at all spatial frequencies both under glare and nonglare conditions (p < 0.05). The mean refractive astigmatism significantly decreased from ‒1.01 ± 1.3 to ‒0.79 ± 0.71, postoperatively (p = 0.029). In patients with marginal reflex distance < 2 mm, mean contrast sensitivity was increased (p < 0.001) and mean astigmatism was decreased significantly (p < 0.001) compared with those with ⩾ 2 mm. Higher order aberrations decreased significantly from 0.62 ± 0.41 µm to 0.55 ± 0.38 µm (p = 0.038) after blepharoplasty. Root mean square of the vertical trefoil (p = 0.038), vertical coma (p = 0.002), horizontal trefoil (p = 0.027), third-order aberration (p = 0.005), secondary vertical stigmatism (p = 0.001), spherical aberration (p = 0.023), secondary horizontal astigmatism (p = 0.002), fourth-order aberration (p = 0.024), vertical pentafoil (p = 0.015), secondary horizontal coma (p = 0.035), secondary horizontal trefoil (p = 0.030), and horizontal pentafoil (p = 0.048) were decreased significantly. Conclusion: Upper eyelid blepharoplasty in patients with dermatochalasis has a significant improvement in visual function in terms of contrast sensitivity, astigmatism, and higher order aberrations.

Characterizing Objective and Self-Reported Levels of Physical Activity Among Florida Firefighters Across Weight Status Category: A Cross-Sectional Pilot Study

2020 ◽  
Vol 68 (11) ◽  
pp. 513-518
Author(s):  
Hannah Kling ◽  
Katerina Santiago ◽  
Leonor Benitez ◽  
Natasha Schaefer Solle ◽  
Alberto J. Caban-Martinez
Keyword(s):  
Physical Activity ◽  
Pilot Study ◽  
Repeated Measures ◽  
Weight Status ◽  
Healthy Weight ◽  
Cross Sectional ◽  
The Difference ◽  
Objectively Measured ◽  
Probabilistic Sample

Background: Firefighters suffer from a disproportionally high burden of chronic diseases that could be prevented from regular bouts of physical activity (PA). The goal(s) of this pilot study were to (a) describe typical PA levels in professional paid firefighters, and (b) assess their ability to estimate their own levels of PA. Methods: A repeated measures study design was used to assess self-reported and objectively measured levels of PA from a non-probabilistic sample of firefighters ( n = 18) over 1 week. Objective measures of PA, measured by accelerometry were defined as the number of minutes spent in sedentary, light, moderate, and vigorous PA. Firefighters completed a follow-up questionnaire recording their self-reported levels of PA. Results: Obese (body mass index [BMI] > 30 kg/m2) firefighters spent 8,033 ± 2,543 minutes/week in sedentary activity, overweight (BMI = 25–29 kg/m2) firefighters 6,533 ± 1,587 minutes/week, and healthy weight (BMI = 18.5–24.9 kg/m2) firefighters 5,846 ± 1,160 minutes/week. The difference in self-reported weekly minutes spent in light, moderate, and vigorous activity and objectively measured minutes in activity was calculated. Healthy weight firefighters reported the least difference (1,924 minutes/week), followed by the overweight (3,884 minutes/week) and obese (5,749 minutes/week). Conclusion/Application to Practice: Firefighters poorly estimated their true level of PA compared with their objectively measured PA and obese firefighters reported the greatest inconsistency. Occupational health nurses should aim to support firefighters in achieving PA levels that assist firefighters to achieve a healthy weight and educate them about what it means to be engaged in each level of PA.

A Survey-Based Method for Measuring and Understanding Brand Equity and Its Extendibility

1994 ◽  
Vol 31 (2) ◽  
pp. 271-288 ◽  
Author(s):  
Chan Su Park ◽  
V. Srinivasan
Keyword(s):  
Brand Equity ◽  
Convergent Validity ◽  
Product Category ◽  
Added Value ◽  
Brand Preference ◽  
Good Reliability ◽  
Attribute Levels ◽  
The Difference ◽  
Definition Of ◽  
Objectively Measured

The authors develop a new survey-based method for measuring and understanding a brand's equity in a product category and evaluating the equity of the brand's extension into a different but related product category. It uses a customer-based definition of brand equity as the added value endowed by the brand to the product as perceived by a consumer. It measures brand equity as the difference between an individual consumer's overall brand preference and his or her brand preference on the basis of objectively measured product attribute levels. To understand the sources of brand equity, the approach divides brand equity into attribute-based and nonattribute-based components. The method provides the market share premium and the price premium attributable to brand equity. The survey-based results from applying the method to the toothpaste and mouthwash categories show that the proposed approach has good reliability, convergent validity, and predictive validity.

scholarly journals First Results after Implantation of Hydrophilic and Hydrophobic Trifocal Intraocular Lenses: Visual and Optical Performance

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Francisco Poyales ◽  
Ricardo Pérez ◽  
Israel López-Brea ◽  
Ying Zhou ◽  
Nuria Garzón
Keyword(s):  
Visual Acuity ◽  
Spherical Aberration ◽  
Optical Design ◽  
Intraocular Lenses ◽  
Optical Performance ◽  
Refractive Outcomes ◽  
Wide Range ◽  
First Results ◽  
Defocus Curve ◽  
Quality Assessments

Purpose. To compare postcataract surgery visual and optical performance between two trifocal intraocular lenses (IOLs) with the same optical design: a hydrophobic acrylic glistening-free IOL and a hydrophilic acrylic IOL. Methods. Patients were bilaterally implanted with either the hydrophobic or the hydrophilic IOL. The data of the patients’ right eyes were evaluated. Visual quality assessments included refractive outcomes, monocular visual acuity (VA) at far, intermediate, and near distances, defocus curve, aberrations (spherical aberration (SA)), root mean square (RMS) of corneal, internal, and total higher-order aberrations (HOAs)), and tilt of IOL. Results. Fifty-one patients were included in the analysis: 26 patients implanted with the hydrophobic IOL and 25 patients implanted with the hydrophilic IOL. At 1 month, no statistically significant differences were found for monocular uncorrected and corrected VA at distance, distance-corrected VA at intermediate and near, defocus curve, manifest spherical equivalent, total SA, and RMS of the total, internal, and corneal HOA. The defocus curve of both groups showed a visual acuity of 0.3 logMAR or better in the intermediate range from 0.5 to −2.5 D of vergence level with no significant differences between the groups. Compared to the hydrophilic group, y-direction tilt was significantly higher in the hydrophobic group ( p = 0.027 ). The total tilt and x-axis tilt did not differ between the groups. Conclusion. Both IOLs demonstrated an excellent quality of vision and provided the patient with a wide range of vision.

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