scholarly journals Night vision in barn owls: Visual acuity and contrast sensitivity under dark adaptation

2012 ◽  
Vol 12 (13) ◽  
pp. 4-4 ◽  
Author(s):  
J. Orlowski ◽  
W. Harmening ◽  
H. Wagner
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Dark Adaptation ◽  
Night Vision ◽  
Barn Owls

scholarly journals Visual Function and Macular Carotenoid Changes in Eyes with Retinal Drusen—An Open Label Randomized Controlled Trial to Compare a Micronized Lipid-Based Carotenoid Liquid Supplementation and AREDS-2 Formula

Nutrients ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3271
Author(s):  
Pinakin Gunvant Davey ◽  
Thomas Henderson ◽  
Drake W. Lem ◽  
Rebecca Weis ◽  
Stephanie Amonoo-Monney ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Dark Adaptation ◽  
Age Related Macular Degeneration ◽  
Visual Performance ◽  
Control Group ◽  
Open Label ◽  
Treatment Groups ◽  
Age Related ◽  
Retinal Drusen

Purpose: To compare the changes in visual and ocular parameters in individuals with retinal drusen who were treated with two commercially available nutritional supplements. Methods: An open-label, single-center, randomized, parallel-treatment with an observational control group design was utilized. The treatment groups included individuals with fine retinal drusen sub-clinical age-related macular degeneration (AMD), while the control group consisted of ocular normal individuals. The treatment groups were randomly assigned to the micronized lipid-based carotenoid supplement, Lumega-Z (LM), or the PreserVision Age-Related Eye Disease Study 2 (AREDS-2) soft gel (PV). Visual performance was evaluated using the techniques of visual acuity, dark adaptation recovery and contrast sensitivity, at baseline, three months, and six months. Additionally, the macular pigment optical density (MPOD) was measured. The control group was not assigned any carotenoid supplement. The right eye and left eye results were analyzed separately. Results: Seventy-nine participants were recruited for this study, of which 68 qualified and 56 participants had useable reliable data. Of the individuals who completed this study, 25 participants belonged to the LM group, 16 belonged to the PV group, and 15 to the control group. The LM group demonstrated statistically significant improvements in contrast sensitivity function (CSF) in both eyes at six months (p < 0.001). The LM group displayed a positive linear trend with treatment time in CSF (p < 0.001), with benefits visible after just three months of supplementation. Although there was a trend showing improvement in CSF in the PV group, the change was not significant after a Bonferroni-corrected p-value of p < 0.00625. Visual acuity, dark adaptation recovery and MPOD did not significantly improve in either treatment groups. Conclusion: The LM group demonstrated greater and faster benefits in visual performance as measured by CSF when compared to the PV group. This trial has been registered at clinicaltrials.gov (NCT03946085).

Thresholds and Resolution in Human Vision: A New Approach to Night Vision Testing

1974 ◽  
Vol 16 (1) ◽  
pp. 56-64
Author(s):  
Thorne Shipley
Keyword(s):  
Visual Acuity ◽  
Individual Differences ◽  
Dark Adaptation ◽  
Night Vision ◽  
Human Vision ◽  
Adaptation Process ◽  
New Approach

Visual acuity dark adaptation in the fovea was studied in immediate temporal alternation with foveal threshold adaptation. This method avoids some of the inconsistencies of earlier work and produces an index of individual differences in visual performances for untrained and unselected observers. Moreover, the results help to display the separate contributions of photochemical and neurological factors to the dark-adaptation process.

Assessing the Effect of Incompatible Light on Night Vision Goggle Performance

1997 ◽  
Vol 41 (2) ◽  
pp. 1098-1102
Author(s):  
Randall W. Gibb ◽  
Jack D. Reising
Keyword(s):  
Visual Acuity ◽  
Sample Size ◽  
Contrast Sensitivity ◽  
Night Vision ◽  
Time Sample ◽  
Spatial Frequencies ◽  
Two Measures ◽  
Complete Index

Current specifications indicate that cockpit lighting designed for night vision goggle (NVG) operations is compatible with NVGs if it does not degrade NVG-aided visual acuity (VA). This study compared two measures of VA; USAF Tri-Bar Chart and NVG Chart. NVG-aided contrast sensitivity (CS) also was assessed; three CS charts having spatial frequencies (SF) of 3, 6, and 12 cycles/degree (cpd) were developed. VA and CS were measured with either low or high levels of incompatible light present. Results revealed that performance did not differ between the two VA measures. Under low incompatible light, CS was degraded only for the high SF. Under high incompatible light, CS was degraded for all SFs. These results suggest that the choice of VA measure should depend upon evaluation factors (e.g., available time, sample size). CS can be used as an alternative to VA and may provide a more complete index of cockpit lighting compatibility.

Pediatric Cataract Surgery: Comparison between Ages at Surgery and Contrast Sensitivity Outcomes

2019 ◽  
Vol 43 (1) ◽  
pp. 50
Author(s):  
Aquirina Caesari Putri ◽  
Rozalina Loebis
Keyword(s):  
Visual Acuity ◽  
Cataract Surgery ◽  
Contrast Sensitivity ◽  
Cataract Extraction ◽  
Significant Negative Correlation ◽  
Natural World ◽  
P Value ◽  
Pediatric Cataract ◽  
Low Contrast ◽  
Significant Difference

Background: Pediatric cataracts are major causes of children’s blindness. Surgery has proven to be beneficial in terms of visual function prognosis. Contrast sensitivity evaluation after surgery is as important as visual acuity considering that natural world consists of various objects in low-to-medium contrasts. The purpose of this study is to analyze the difference of contrast sensitivity outcomes based on ages at surgery. Method: Retrospective data of children with pediatric developmental cataract from July 2013 to November 2015 were collected. All children who underwent cataract surgery at 60-months-old or less were randomized into two groups, ≤24 months and >24-to-60 months. Contrast sensitivity was then examined with preferential-looking method using Hiding Heidi low-contrast test face chart. The main outcome measures were contrast sensitivity of both groups. Age-at-evaluation, cataract onset, duration of follow-up, duration of deprivation and visual acuity were also noted. Result: Of 14 children (23 eyes), 11 eyes (47,8%) were in ≤24 months group, 12eyes (52,2%) were in >24-to-60 months group. All eyes underwent cataract extraction and similar type of intraocular lens implantation. Mean age-at-surgery was 28,2 months±16,8 (SD). Mean contrast sensitivity for each group was 47,50 %±42,29 and 18,33%±27,38, respectively, with p-value 0,031. Further analysis of Spearman’s correlation test demonstrated significant negative correlation (rs = -0,559; p = 0,006) between the two groups. Conclusion: There was statistically significant difference in contrast sensitivity between those who underwent surgery at ≤24 months and >24-to-60 months. Children who underwent surgery at older ages tend to have better contrast sensitivity afterwards.

Reproducibility of Night Vision Goggle Visual Acuity Measurements Using Landolt C's

1999 ◽  
Author(s):  
Alan Pinkus ◽  
H. L. Task ◽  
Sharon Dixon ◽  
Charles Goodyear
Keyword(s):  
Visual Acuity ◽  
Night Vision

Visual Acuity for High-Contrast Tri-bar Targets Illuminated with Spectra Simulating Night Vision Goggle (NVG) Displays and the No-moon Night Sky

2010 ◽  
Author(s):  
V. G. CuQlock-Knopp ◽  
Edward Bender ◽  
John Merritt ◽  
Jennifer Smoot
Keyword(s):  
Visual Acuity ◽  
Night Vision ◽  
High Contrast ◽  
Night Sky
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