scholarly journals Factors Influencing Contrast Sensitivity Function in Eyes with Mild Cataract

2021 ◽  
Vol 10 (7) ◽  
pp. 1506
Author(s):  
Kazutaka Kamiya ◽  
Fusako Fujimura ◽  
Takushi Kawamorita ◽  
Wakako Ando ◽  
Yoshihiko Iida ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Sensitivity Function ◽  
Contrast Sensitivity Function ◽  
Partial Regression Coefficient ◽  
Explanatory Variables ◽  
Uncorrected Visual Acuity ◽  
The Mean ◽  
The Relationship ◽  
Relevant Factors

This study was aimed to evaluate the relationship between the area under the log contrast sensitivity function (AULCSF) and several optical factors in eyes suffering mild cataract. We enrolled 71 eyes of 71 patients (mean age, 71.4 ± 10.7 (standard deviation) years) with cataract formation who were under surgical consultation. We determined the area under the log contrast sensitivity function (AULCSF) using a contrast sensitivity unit (VCTS-6500, Vistech). We utilized single and multiple regression analyses to investigate the relevant factors in such eyes. The mean AULSCF was 1.06 ± 0.16 (0.62 to 1.38). Explanatory variables relevant to the AULCSF were, in order of influence, logMAR best spectacle-corrected visual acuity (BSCVA) (p < 0.001, partial regression coefficient B = −0.372), and log(s) (p = 0.023, B = −0.032) (adjusted R2 = 0.402). We found no significant association with other variables such as age, gender, uncorrected visual acuity, nuclear sclerosis grade, or ocular HOAs. Eyes with better BSCVA and lower log(s) are more susceptible to show higher AULCSF, even in mild cataract subjects. It is indicated that both visual acuity and intraocular forward scattering play a role in the CS function in such eyes.

Contrast sensitivity function and visual acuity of the opossum

1982 ◽  
Vol 22 (11) ◽  
pp. 1371-1377 ◽  
Author(s):  
L.C.L. Silveira ◽  
C.W. Picanço-Diniz ◽  
E. Oswaldo-Cruz
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Sensitivity Function ◽  
Contrast Sensitivity Function

scholarly journals Long-Term Evaluation of Visual Outcomes and Patient Satisfaction after Binocular Implantation of a Bioanalogic Lens

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Sylwia Wagner ◽  
Grzegorz Wagner ◽  
Ewa Mrukwa-Kominek
Keyword(s):  
Visual Acuity ◽  
Patient Satisfaction ◽  
Contrast Sensitivity ◽  
Case Series ◽  
Spatial Frequencies ◽  
Uncorrected Visual Acuity ◽  
Term Evaluation ◽  
The Mean

Purpose. Long-term evaluation of the visual refractive outcomes and the quality of life after implantation of the WIOL-CF (Medicem, Czech Republic) in both eyes. Design. retrospective, nonrandomized noncomparative case series. Methods. 50 eyes of 25 patients, including 11 women (44%) and 14 men (56%). The age range of the patients was 38 to 77 years (mean age 55.48 ± 10.97 years). All patients underwent bilateral implantation of the WIOL-CF. Exclusion criteria were previous ocular surgeries except for cataract surgery and refractive lens exchange, irregular corneal astigmatism of >1.0 diopter, and ocular pathologies or corneal abnormalities. Postoperative examinations were performed at 14 days and 3, 6, 12 months of surgery; the last follow-up was between 24 and 36 months after the procedure. All exams included manifest refraction, monocular uncorrected visual acuity (UCVA) and distance-corrected visual acuity (DCVA) in 5 m (Snellen), monocular uncorrected visual acuity in 70 cm and 40 cm (Jeager) and binocular UCVA, DCVA in 5 m, 70 cm, and 40 cm, binocular contrast sensitivity (CS) under photopic conditions, binocular defocus curves, high-order aberrations, quality-of-vision VF-14 questionnaire, and spectacle independence. Results. Significant improvement in monocular visual acuity at all distances was demonstrated; the mean postoperative spherical equivalent was 0.32 ± 0.45D. The postoperative means of binocular distance UCVA and BCVA were also improved ( p  < .001) and so were the mean uncorrected intermediate VA (2.053 ± 1.268) and near uncorrected VA (2.737 ± 1.447). There was a significant improvement in contrast sensitivity at all spatial frequencies and higher-order aberration, compared to preoperative results. Conclusions. The evaluation of a WIOL-CF showed good distance, intermediate, and near visual acuity. Contrast sensitivity increased after surgery in all spatial frequencies. Patient satisfaction was high despite some optical phenomena. The rate of postoperative spectacle independence also turned out high. Financial Disclosure. No author has a financial or proprietary interest in any material or method mentioned.

scholarly journals Contrast Sensitivity Function of the Albino Rat Determined Electrophysiologically

1998 ◽  
Vol 1 ◽  
pp. 11-17 ◽  
Author(s):  
Pilar Herreros de Tejada ◽  
Carmen Muñoz Tedó
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Sensitivity Function ◽  
Contrast Sensitivity Function ◽  
Albino Rats ◽  
Lower Sensitivity ◽  
Experimental Conditions ◽  
Albino Rat ◽  
Spatial Frequencies ◽  
Luminance Threshold

Albinism alters the neural projections of the visual system. The authors wondered how this would affect visual function in rodents. They had previously shown that it doesn't alter the luminance threshold. They now explore visual acuity in the albino rat. In this work, they describe its contrast sensitivity function (CSF), as determined electro-physiologically. They recorded cortical visual evoked potentials (VEP) on six albino rats, stimulated by sinusoidal contrast reversal gratings. The curve showed the same characteristics that this function has in other mammals. Compared with the pigmented rat, the albino reached lower sensitivity values and showed a loss of sensitivity at high spatial frequencies. The estimated cut-off was 0.48 c/°, that is, 0.72 log units below the estimated cut-off for the pigmented rat under similar experimental conditions. VEP and behavioral cut-off were very close, the VEP estimation being slightly higher than the behavioral one.

scholarly journals Effects of Intermediate-Tinted Lenses on Pistol Marksmanship and Visual Performance

2020 ◽  
Author(s):  
Hong Gao ◽  
Jay E Clasing ◽  
Robert N Kang ◽  
Micah J Kinney
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Color Vision ◽  
Sensitivity Function ◽  
Contrast Sensitivity Function ◽  
Light Transmittance ◽  
Viable Option ◽  
Bonferroni Adjustment ◽  
Post Hoc ◽  
Combat Environment

ABSTRACT Introduction The standard issue clear or sun Military Combat Eye Protection (MCEP) is often inadequate in visually challenging training or combat environment. Intermediate-tinted lenses may offer a viable option for warfighters operating in dynamic visual conditions such as moving rapidly from bright sunny areas to darker building interiors in combat. Because the use of intermediate-tinted lenses has been delayed as a result of a potential negative impact on vision performance such as color perception, this investigation evaluated several commercially available intermediate-tinted lenses for operation performance during a U.S. military field training. Test lenses complied with all the requirements of the current MCEP except for the visible light transmittance (VLT) values that ranged between 32 and 62%. Materials and Methods Study subjects consisted of 22 service members who attended a military Close Combat and Marksmanship training course in May 2019. Visual and pistol marksmanship performance of three intermediate-tinted lenses (Eye Safety Systems [ESS] Copper [32% VLT], Oakley Prizm TR45 [44% VLT], and ESS Bronze [62% VLT]) was compared to that of a standard issue MCEP, ESS Clear (90% VLT). Quick contrast sensitivity function test was used to assess quality vision (AULCSF, area under a log contrast sensitivity function) and visual acuity (CSF Acuity). Color vision was assessed by Cone Contrast Test. Pistol marksmanship (Bill Drill) was used for performance testing. A pre-survey inquired about MCEP use, and a MCEP survey during the pistol marksmanship testing inquired about lens performance and ranking. Results AULCSF and CSF Acuity were significantly affected by the lenses (general linear model, repeated measures, P &lt; .05). Bonferroni post hoc test showed a significant reduction of binocular AULCSF from ESS Clear to Oakley Prizm TR45 (P = .003) and ESS Copper (P &lt; .001) and a significant reduction in binocular CSF Acuity from ESS Clear to ESS Copper (P = .001). Color vision and pistol marksmanship performance were not significantly affected by wearing different lenses (P &gt; .05). Subjectively, there were no statistically significant differences among study lenses in perceived “clarity of vision,” “ability to clearly identify the target,” or “overall performance” (Friedman test and Wilcoxon signed-rank post hoc test with Bonferroni adjustment, P &gt; .017). Participants ranked Prizm TR45 (44% VLT) and ESS Bronze (62% VLT) lenses significantly more favorably than EES Clear (P = .001 and P = .009). Conclusions Quality of vision and visual acuity decreased with darker lenses; however, the study lenses had insignificant impacts on pistol marksmanship and subjective acceptance. Our surveys indicated that Intermediate-tinted lenses were operationally acceptable and preferred over a standard issue MCEP. While more evaluations for color vision deficient subjects are needed, overall results suggest that commercially available intermediate-tinted lenses may be a viable option to enhance protection and performance in a visually dynamic combat environment.

Masking by Uniform Field Flicker: Some Practical Problems

Perception ◽  
1987 ◽  
Vol 16 (5) ◽  
pp. 641-647 ◽  
Author(s):  
David R Badcock ◽  
Elizabeth Sevdalis
Keyword(s):  
Visual System ◽  
Contrast Sensitivity ◽  
Human Visual System ◽  
Sensitivity Function ◽  
Relative Performance ◽  
Contrast Sensitivity Function ◽  
Uniform Field ◽  
Spatial Frequencies ◽  
The Mean ◽  
Mean Luminance

The technique of uniform field flicker (UFF) masking has frequently been used to address issues concerning the relative performance of sustained and transient neural channels in the human visual system. Unfortunately there has been an artifact in the implementation of this method in most published experiments which has meant that the contrast of the target has been flickered in synchrony with the mean luminance. A study is reported in which the artifact was corrected and the effects of UFF masking on the contrast sensitivity function then examined. With this correction, masking was still restricted to low spatial frequencies but it was much weaker than reported originally. It is argued that the original evidence suggesting that UFF masking can be used to examine the functioning of transient and sustained channels has not been interpreted correctly and that the basis for such a claim is weak.

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