scholarly journals Prevalence of Visual Acuity Loss or Blindness in the US

Author(s):  
Abraham D. Flaxman ◽  
John S. Wittenborn ◽  
Toshana Robalik ◽  
Rohit Gulia ◽  
Robert B. Gerzoff ◽  
...  
2018 ◽  
Vol 10 (4) ◽  
Author(s):  
Paulo Ramiler Silva ◽  
Tiago Farias ◽  
Fernando Cascio ◽  
Levi Dos Santos ◽  
Vinícius Peixoto ◽  
...  

The visual acuity loss enables the brain to access new pathways in the quest to overcome the visual limitation and this is wellknown as neuroplasticity which have mechanisms to cortical reorganization. In this review, we related the evidences about the neuroplasticity as well as cortical anatomical differences and functional repercussions in visual impairments. We performed a systematic review of PUBMED database, without date or status publication restrictions. The findings demonstrate that the visual impairment produce a compensatory sensorial effect, in which non-visual areas are related to both cross (visual congenital) and multimodal (late blind) neuroplasticity.


2018 ◽  
Vol 235 (04) ◽  
pp. 416-419 ◽  
Author(s):  
Nathalie Voide ◽  
Nicole Hoeckele ◽  
Pierre-François Kaeser

Abstract Background The Spot Vision Screener (SVS) is designed to detect significant ametropia, anisometropia, and strabismus in non-dilated eyes. This study evaluates the efficacy of the SVS in paediatric visual screening. Patients and Methods All children screened during the paediatric visual screening day in Lausanne in 2016 were evaluated with the SVS, conventional monocular autorefractors, and clinical orthoptic examination. Recommendations for a further eye examination of the SVS were compared with those issued from traditional clinical screenings (monocular refraction and orthoptic examination). Results One hundred and sixty-eight consecutive children were included. The median age was 3.9 years. The SVS median spherical equivalent (SE) was + 0.25 D OU and it detected seven cases of (4.2%) anisometropia (SE difference ≥ 1 D). The conventional monocular autorefractor median SE was − 0.13 D OU and 20 cases of anisometropia (11.9%) were detected. Refraction could not be measured in 1.2% of patients with SVS versus 17.2% with monocular refractors. The SVS screened two manifest strabismus cases against five manifest and > 100 latent strabismus with orthoptic examination. As expected, the SVS was unable to assess reactions to monocular occlusion, visual acuity, and stereovision as well as to detect ocular motility disorders without strabismus in the primary position, and missed two cases of abnormal Brückner reflexes. Overall, the SVS identified 66 suspect patients (39.3%) against 102 (60.7%) after complete clinical examination. Conclusions The SVS can be a useful objective screening tool for non-ophthalmologists. However, because it fails to detect ocular motility troubles, organic visual acuity loss, or to assess the visual potential, it should only be used in association with a clinical examination, even in routine screening procedures.


2011 ◽  
Vol 14 (12) ◽  
pp. 2236-2244 ◽  
Author(s):  
Myriam Fillion ◽  
Mélanie Lemire ◽  
Aline Philibert ◽  
Benoît Frenette ◽  
Hope Alberta Weiler ◽  
...  

AbstractObjectiveTo examine the associations between near and distant visual acuity and biomarkers of Hg, Pb, n-3 fatty acids and Se from the local diet of fish-eating communities of the Tapajós River in the Brazilian Amazon.DesignVisuo-ocular health and biomarkers of Hg (hair, whole blood, plasma), Pb (whole blood), Se (whole blood and plasma) and n-3 fatty acids (plasma total phospholipids) were assessed in a cross-sectional study.SettingLower Tapajós River Basin (State of Pará, Brazil), May to July 2006.SubjectsTwo hundred and forty-three adults (≥15 years) without diagnosed age-related cataracts or ocular pathologies.ResultsNear visual acuity was negatively associated with hair Hg and positively associated with %DHA, with a highly significant Log Hg × age interaction term. Stratifying for age showed that while young people presented good acuity, for those aged ≥40 years, clinical presbyopia was associated with hair Hg ≥ 15 μg/g (OR = 3·93, 95 % CI 1·25, 14·18) and %DHA (OR = 0·37, 95 % CI 0·11, 1·11). A similar age-related pattern was observed for distant visual acuity in relation to blood Pb, but the evidence was weaker.ConclusionsThese findings suggest that Hg and Pb may affect visual acuity in older persons, while DHA appears to be protective for near visual acuity loss. In this population, with little access to eye care, diet may have an important influence on visuo-ocular ageing.


2019 ◽  
Vol 35 (2) ◽  
pp. 109-114 ◽  
Author(s):  
Renata L. B. Moraes ◽  
Ramon C. Ghanem ◽  
Vinicius C. Ghanem ◽  
Marcony R. Santhiago

1997 ◽  
Vol 7 (3) ◽  
pp. 203-210 ◽  
Author(s):  
R. Brancato ◽  
F. Carones ◽  
A. Morico ◽  
E. Venturi ◽  
L. Vigo ◽  
...  

Purpose. This paper presents the results of the first human trial on the correction of hyperopia using an erodible mask excimer laser delivery system coupled to an axicon. Methods. We treated 17 eyes of 17 patients (age range 34–62 years) for the correction of +3.21 ± 1.04 D (range +1.00 to +4.00 D). The hyperopic correction was made using an erodible mask inserted on the laser optical pathway, to produce a circular ablation measuring 6.5 mm in diameter. An axicon was then used to create a blend transition zone from 6.5 mm up to 9.4 mm in diameter. Eyes were evaluated at one, three and six months after surgery. Results. Reepithelization was always observed by the fifth postoperative day, despite the large area of deepithelization (diameter 9.5 mm). Mean refractive error one month after treatment was −2.44 ± 1.59 D (range 0.00 to −6.50 D). Five eyes (29.4%) had a best corrected visual acuity loss more than two to three lines; all eyes showed mild annular haze not involving the central part of the cornea. Six months after treatment, mean refractive error was −0.88 ± 0.99 D (range +0.50 to −3.00 D). Compared to preoperative status, 13 eyes (76.5%) showed an improvement in uncorrected distance visual acuity (1–8 lines), and 14 eyes (82.4%) showed an improvement in uncorrected vision at reading distance (3–7 lines). Two eyes (11.7%) showed a best corrected visual acuity loss of two of three lines. Conclusions. These preliminary results indicate this approach is effective in reducing hyperopia, while its predictability has still to be proved in a larger treatment group with longer follow-up. A cautious approach to this technique is still advisable, especially for higher hyperopic corrections, in view of the large best corrected visual acuity loss seen in two eyes at six months.


2019 ◽  
Vol 137 (9) ◽  
pp. 1078
Author(s):  
Anat Loewenstein ◽  
Jean-François Korobelnik ◽  
Annabelle A. Okada

2020 ◽  
Vol 267 (S1) ◽  
pp. 265-272
Author(s):  
D. Starkov ◽  
M. Snelders ◽  
F. Lucieer ◽  
A. M. L. Janssen ◽  
M. Pleshkov ◽  
...  

Abstract Introduction Bilateral vestibulopathy (BVP) can affect visual acuity in dynamic conditions, like walking. This can be assessed by testing Dynamic Visual Acuity (DVA) on a treadmill at different walking speeds. Apart from BVP, age itself might influence DVA and the ability to complete the test. The objective of this study was to investigate whether DVA tested while walking, and the drop-out rate (the inability to complete all walking speeds of the test) are significantly influenced by age in BVP-patients and healthy subjects. Methods Forty-four BVP-patients (20 male, mean age 59 years) and 63 healthy subjects (27 male, mean age 46 years) performed the DVA test on a treadmill at 0 (static condition), 2, 4 and 6 km/h (dynamic conditions). The dynamic visual acuity loss was calculated as the difference between visual acuity in the static condition and visual acuity in each walking condition. The dependency of the drop-out rate and dynamic visual acuity loss on BVP and age was investigated at all walking speeds, as well as the dependency of dynamic visual acuity loss on speed. Results Age and BVP significantly increased the drop-out rate (p ≤ 0.038). A significantly higher dynamic visual acuity loss was found at all speeds in BVP-patients compared to healthy subjects (p < 0.001). Age showed no effect on dynamic visual acuity loss in both groups. In BVP-patients, increasing walking speeds resulted in higher dynamic visual acuity loss (p ≤ 0.036). Conclusion DVA tested while walking on a treadmill, is one of the few “close to reality” functional outcome measures of vestibular function in the vertical plane. It is able to demonstrate significant loss of DVA in bilateral vestibulopathy patients. However, since bilateral vestibulopathy and age significantly increase the drop-out rate at faster walking speeds, it is recommended to use age-matched controls. Furthermore, it could be considered to use an individual “preferred” walking speed and to limit maximum walking speed in older subjects when testing DVA on a treadmill.


Sign in / Sign up

Export Citation Format

Share Document