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At least 1,351 records · Page 75Linked to original sources
PubMed1998

Visual acuity and the essentiality of docosahexaenoic acid and arachidonic acid in the diet of term infants.

The need for a dietary supply of docosahexaenoic acid (DHA) and arachidonic aid (AA) in term infants was evaluated in a double-masked randomized clinical trial of the effects of supplementation of term infant formula with DHA (0.35% of total fatty acids) or with DHA (0.36%) and AA (0.72%) on visual acuity development. One hundred and eight healthy term infants were enrolled in the study; 79 were exclusively formula-fed from birth (randomized group) and 29 were exclusively breast-fed (gold standard group). Infants were evaluated at four time points during the first 12 mo of life for blood fatty acid composition, growth, sweep visual evoked potential (VEP) acuity, and forced choice preferential looking acuity. Supplementation of term infant formula with DHA or with DHA and AA during the first 4 mo of life yields clear differences in total red blood cell (RBC) lipid composition. Supplementation of term infant formula with DHA or with DHA and AA also yields better sweep VEP acuity at 6, 17, and 52 wk of age but not at 26 wk of age, when acuity development reaches a plateau. The RBC lipid composition and sweep VEP acuity of supplemented infants was similar to that of human milk-fed infants, whereas the RBC lipid composition and sweep VEP acuity of unsupplemented infants was significantly different from human milk-fed infants. Differences in acuity among diet groups were too subtle to be detected by the forced choice preferential looking protocol. Infants in all diet groups had similar rates of growth and tolerated all diets well. Thus, early dietary intake of preformed DHA and AA appears necessary for optimal development of the brain and eye of the human infant.

Arachidonic Acid↗
PubMed2003

Visual acuity, optical, and eye health readiness in the military.

Optimum vision readiness is essential on today's technologically advanced battlefield. A vision readiness screening of 4,825 active duty personnel at 13 Department of Defense sites from September through December 1997 revealed 4,021 (83.3%) not vision ready: 500 (10.4%) had substandard visual acuity, 1,249 (25.9%) had deficient optical devices, and 3,562 (73.8%) had eye health-related deficiencies. This suggests a more effective ongoing vision readiness process should be implemented to ensure all personnel are vision ready prior to deployment.

Contact Lenses↗
PubMed2000

Reliability of Snellen charts for testing visual acuity for driving: prospective study and postal questionnaire.

OBJECTIVES: To assess the ability of patients with binocular 6/9 or 6/12 vision on the Snellen chart (Snellen acuity) to read a number plate at 20.5 m (the required standard for driving) and to determine how health professionals advise such patients about driving. DESIGN: Prospective study of patients and postal questionnaire to healthcare professionals. SUBJECTS: 50 patients with 6/9 vision and 50 with 6/12 vision and 100 general practitioners, 100 optometrists or opticians, and 100 ophthalmologists. SETTING: Ophthalmology outpatient clinics in Sheffield. MAIN OUTCOME MEASURES: Ability to read a number plate at 20.5 m and health professionals' advice about driving on the basis of visual acuity. RESULTS: 26% of patients with 6/9 vision failed the number plate test, and 34% with 6/12 vision passed it. Of the general practitioners advising patients with 6/9 vision, 76% said the patients could drive, 13% said they should not drive, and 11% were unsure. Of the general practitioners advising patients with 6/12 vision, 21% said the patients could drive, 54% said they should not drive, and 25% were unsure. The level of acuity at which optometrists, opticians, and ophthalmologists would advise drivers against driving ranged from 6/9(-2) (ability to read all except two letters on the 6/9 line of the Snellen chart) to less than 6/18. CONCLUSIONS: Snellen acuity is a poor predictor of an individual's ability to meet the required visual standard for driving. Patients with 6/9 vision or less should be warned that they may fail to meet this standard, but those with 6/12 vision should not be assumed to be below the standard.

Automobile Driving↗
PubMed2004

[Visual acuity, quality of life, and patient satisfaction after PDT treatment in AMD patients].

BACKGROUND: The efficacy of PDT to prevent the progression of AMD has been established. This study now assesses the patients' quality of life and self-reported satisfaction after PDT. MATERIAL AND METHODS: All patients who underwent PDT during 2000 and 2001 at the University Eye Hospital of Mainz were interviewed using an AMD-specific modification of a standardized 82-item questionnaire on quality of life and satisfaction in ophthalmological patients. Different aspects of those parameters were derived as scores, which were then related to clinical outcome parameters. RESULTS: During the period of PDT treatment, the median decrease in visual acuity was three stages in the patients examined. Patients who reported a subjective increase in visual function during this period showed for example a median "private flexibility" score of 1.86, and patients with the subjective impression of a decrease in visual function a median score of 2.71. CONCLUSION: The established clinical efficacy of PDT treatment to prevent AMD progression coincides with an encouraging patient satisfaction after the treatment.

Activities of Daily Living↗
PubMed1976

Visual acuity and colour vision tests--a preliminary report.

Results are reported of a preliminary survey of colour vision changes in fifteen patients with central serous retinopathy. Colour vision was monitored with the HRR plates, 100-hue test and Nagel anomaloscope. In those patients revealing an acquired dyschromatopsia the defect had a tritan-like response. However, diagnosis is made difficult because of the positively correlated trend between 100-hue error score and visual acuity.

Adult↗
PubMed1983

Prevalence of severely impaired visual acuity among diabetic patients in Fukuoka Prefecture with special emphasis on diabetic retinopathy: a survey by the Fukuoka Diabetes Clinic Group.

From December 1981 to January 1982, 3841 diabetic patients were seen in 16 diabetic clinics in Fukuoka Prefecture. Among them, 3289 diabetics had been examined for the presence of ophthalmological complications during the past year, and 979 cases (29.8%) had diabetic retinopathy, in which the proliferative type manifested itself in 152 cases (4.6%). Of 3841 diabetics in our clinics, there were 275 cases (7.2%) with severely weakened visual acuity (assessed by corrected acuity below 0.1), of which 153 cases (4.0%) resulted from diabetic retinopathy. Of these, 92 (2.4% of total diabetics) had visual defects in both eyes. Analyses on these 153 cases revealed several features, i.e., there were 10 cases with maculopathy and 4 cases with secondary rubeotic glaucoma, the age of the patients was 55.9 +/- 11.5 (mean +/- S.D.) years, and the presumed duration of diabetes, time lapse until appearance of visual defect(s) from onset of diabetes and the untreated period were 13.8 +/- 6.6 (n = 150), 10.5 +/- 6.0 (n = 124) and 4.2 +/- 4.9 (n = 101) years, respectively.

Blindness↗
PubMed2004

Low contrast visual acuity in pseudophakic patients implanted with an anterior surface modified prolate intraocular lens.

PURPOSE: To determine whether implantation of a new intraocular lens (IOL) with a modified prolate anterior surface, designed to reduce the positive spherical aberration of the pseudophakic eyes, results in improved contrast sensitivity assessed in terms of low contrast visual acuity (VA). METHODS: We carried out an intraindividual study of 12 patients with bilateral cataracts, randomized to receive a prolate anterior surface IOL (Tecnis Z9000, Pharmacia) in one eye and a biconvex spherical surface IOL (CeeOn 911 A, Pharmacia) in the other. High and low contrast VA was assessed under photopic conditions, before and after pupil dilation. RESULTS: After mydriasis, the Technis Z9000 provided significantly better low contrast VA at contrast levels < or = 25%. No significant difference was found under normal pupil conditions. CONCLUSION: Our results confirm the hypothesis that the spherical aberration of the eye after cataract surgery can be reduced by an anterior prolate surface IOL.

Aged↗
PubMed2006

Long-term efficacy and visual acuity following transscleral diode laser photocoagulation in cases of refractory and non-refractory glaucoma.

AIMS: Transscleral diode laser cyclophotocoagulation (TSCP) is widely accepted in the treatment of refractory glaucoma especially in eyes with poor vision. However, until recently, there has been a reluctance to extend its use to eyes with good visual acuity (VA). The aims of this study were to evaluate the long-term efficacy and safety of TSCP for a range of glaucoma conditions, with particular emphasis on post-treatment VA in seeing eyes. METHODS: A retrospective analysis of case notes of 74 treated eyes was conducted over a period of 4-30 months (mean 12.5 months). RESULTS: Mean (SD) intraocular pressure (IOP) was reduced by 43% from 40.3 (6.7) to 21.1 mmHg (5.4) at the final index visit. Of all patients, 58% had a reduction in glaucoma drops and all discontinued oral Acetazolamide; 9% experienced complications. Mean VA was preserved in the subgroups with good vision, although 3/23 (13%) patients with primary open-angle glaucoma (POAG) lost vision due to cataract and glaucoma progression. There were no cases of hypotony (IOP<or=5 mmHg) or phthisis and only one eye required re-treatment. CONCLUSIONS: TSCP is highly effective and safe for various types of glaucoma, and its use can be extended to eyes with good vision.

Adult↗
PubMed1999

Amblyopia and visual acuity in children with Down's syndrome.

BACKGROUND/AIMS: Amblyopia in people with Down's syndrome has not been well investigated. This study was designed to determine the prevalence and associated conditions of amblyopia in a group of home reared children with Down's syndrome. METHODS: All children in the study group underwent an evaluation of visual acuity. In addition, previous ophthalmological records were reviewed, and a subgroup of children was examined. For the purposes of this study, amblyopia was defined quantitatively as a difference of two Snellen acuity lines between eyes or if unilateral central steady maintained (CSM) vision and a clear fixation preference was observed. A high refractive error was defined as a spherical equivalent more than 3 dioptres and astigmatism more than 1.75 dioptres. Anisometropia was defined as a difference of at least 1.5 dioptres of sphere and/or 1.0 dioptre of cylinder between eyes. 68 children with Down's syndrome between the ages of 5 and 19 years were enrolled in the final study group. RESULTS: Amblyopia was observed in 15 (22%) of 68 patients. An additional 16 (24%) patients had bilateral vision less than 20/50. Strabismus, high refractive errors, and anisometropia were the conditions most commonly associated with decreased vision and amblyopia CONCLUSION: This study suggests that the prevalence of amblyopia is higher than previously reported. Fully 46% of these children with Down's syndrome had evidence of substantial visual deficits. These patients may be at higher risk for visual impairment and should be carefully examined for ophthalmological problems.

Adolescent↗
PubMed1985

Ocular motility, visual acuity and dysfunction of neuropsychological impairment in children with shunted uncomplicated hydrocephalus.

Children with shunted, uncomplicated, communicating hydrocephalus were tested to determine (1) the persistence of neuropsychological impairment and (2) the relationship between neuropsychological functioning, ocular motility, and acuity abnormalities. Eighteen hydrocephalic and 18 individually age- and sex-matched controls were given a neuropsychological battery, repeated after an interval of 1 year. Hydrocephalic children were also tested at the beginning of the second year for strabismus, amblyopia and visual acuity. Their medical records were reviewed for history of ocular motility and/or acuity abnormalities. Hydrocephalic children with normal range IQ were found to have lower verbal IQ, memory, and fine motor skills compared to controls. A history of ocular motility and acuity abnormalities was associated with impaired visuospatial and verbal problem-solving skills.

Achievement↗
PubMed1984

[How do patients assess their visual acuity after intracapsular cataract extraction and correction with eyeglasses].

In the investigation reported here, 115 patients who had undergone cataract surgery at least 1 year previously, and for whom cataract glasses had been prescribed, were asked to give a subjective assessment of their vision. Almost 50% of them mentioned impairment of vision in certain situations (traffic, descending stairs). Altogether, 75.7% of the patients interviewed considered their vision good; only 2.7% felt it was unsatisfactory. Defects characteristic of aphakia correction were also cited by patients with good visual acuity. On the other hand, even patients with relatively poor vision (macular disease) reported that they were satisfied. The patients' adaptation to the change in visual conditions brought about by the cataract glasses can only be described as remarkable.

Aged↗
PubMed2004

Critique of claims of improved visual acuity after hypnotic suggestion.

Psychological approaches to improving vision present an enticing alternative to invasive procedures and corrective lenses; hypnotic suggestion is one such technique. During the past 60 years, multiple studies have documented improvements in the vision of myopic individuals after hypnotic interventions. Given the increasing interest in behavioral and alternative approaches, we have reviewed the pertinent studies to evaluate their validity. We delineate various shortcomings in these reports, including potential methodological caveats, problems with experimental controls, and controversial data interpretation. Overall, the data do not seem to support hypnosis as a viable option for significant long-term improvement of myopia. However, hypnosis can increase one's subjective feeling of enhanced visual acuity by affecting higher cognitive functions, such as attention, memorization, and perceptual learning, which could influence performance on visual tasks.

Attention↗