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At least 1,729 records · Page 96Linked to original sources
PubMed1996

Ocular findings in Down's syndrome.

PURPOSE: To identify the most common ocular findings in a pediatric group of patients with Down's syndrome. METHODS: A total of 152 children with Down's syndrome between two months and 18 years of age prospectively underwent ocular examination, including visual acuity assessment, slit-lamp biomicroscopy, ocular motility, cycloplegic retinoscopy, and ophthalmoscopy. RESULTS: Ocular findings in decreasing prevalence were the following: upward slanting of the palpebral fissure with the outer canthus 2 mm or higher than the inner canthus (82%), epicanthal folds (61%), astigmatism (60%), iris abnormalities (52%), strabismus (38%), lacrimal system obstruction (30%), blepharitis (30%), retinal abnormalities (28%), hyperopia (26%), amblyopia (26%), nystagmus (18%), cataract (13%), and myopia (13%). Visual acuity was assessed, and the Teller acuity cards were the most useful method of examination. The patients younger than five years old had a higher prevalence of hyperopia than did those in other age groups; patients between five and 12 years old had a higher prevalence of astigmatism; and patients older than 12 years of age had more iris abnormalities, strabismus, and cataract. Myopia and myopic astigmatism were more common in the patients with cardiac malformations. CONCLUSION: The early diagnosis of the ocular abnormalities in patients with Down's syndrome, by using Teller acuity cards in assessing visual acuity facilitates the treatment of refractive errors, strabismus, and amblyopia and may minimize handicaps.

Adolescent↗
PubMed2003

Analysis of intraocular lens power calculation in post-radial keratotomy eyes.

PURPOSE: To determine whether refractive complications can be prevented by applying the currently most accurate method of intraocular lens (IOL) power calculation in the post-radial keratotomy (RK) patient. SETTING: Department of Ophthalmology, University of California, Davis, Sacramento, and American Eye Institute, Cedars Sinai Medical Center, Los Angeles, California, USA. METHODS: Twenty-four eyes having cataract surgery after RK were studied retrospectively for the final postcataract refraction and for the target refraction used in selecting the IOL. Nine of the eyes were further studied for the keratometry (K) values obtained with different methods and for the theoretical postoperative refraction with an IOL aiming for plano or -1.50 diopters (D) based on the known flatter calculated K, axial length, power of the implanted IOL, and refraction after cataract surgery. RESULTS: Implantation of an IOL aiming for plano in the 24 post-RK eyes would have resulted in a hyperopic refraction in 83.4% cases. The choice of an IOL targeted at myopia reduced the frequency of hyperopia to 42.0% (24 cases). Selection of an IOL calculated with a flatter calculated K and aiming for plano decreased the frequency of hyperopia to 44.4%; however, aiming for -1.50 D still resulted in hyperopia in 44.4% of eyes (9 cases). CONCLUSIONS: Unintentional hyperopia can be significantly decreased but not eliminated as a complication of post-RK cataract surgery. The accuracy of the IOL power determination can be improved if myopia is targeted as the postcataract surgery refractive error and the flatter calculated K is used in the IOL determination.

Humans↗
PubMedDate not supplied

[Ocular system in Down's syndrome].

The authors presents results of ophthalmological examination of 150 patients with cytogenetically diagnosed Down's syndrome. Refractive errors, requiring correction with glasses, were found in 45.3% of patients. Other ocular changes among which some were qualified for treatment, were observed in 72.7% of cases.

Adolescent↗
PubMed2000

Intraocular lens implantation in children.

Over the past 15 years, lens implant surgery in children has disseminated so much that it is no longer a controversial issue. It has become rather a specialized topic in the widespread field of lens implantation in the general population. To match the excellent results seen in adults, issues such as the surgical technique, the choice of the lens, and dioptric power of that lens, are constantly being refined and adapted to children's growing eyes. Scleral tunnels and small, self-sealing corneal incisions are being replicated in children to benefit from their advantages. Polymethyl methacrylate material remains unrivalled from the point of view of safety and longevity in the human eye. Intraocular lenses (IOLs) with an overall diameter of 12 mm can safely be used in nonmicrophthalmic eyes of children more than 3 years of age. Several investigators now recognize the need for smaller pediatric IOLs for neonates, toddlers, and microphthalmic eyes. Fortunately, modern IOLs are smaller today than they were 15 years ago. The accumulating evidence on the myopic shift that occurs in pseudophakic children have led to an almost unanimous agreement that the IOL power should aim for a certain amount of hypermetropia at time of surgery. The residual refractive error can be corrected with spectacle glasses that are adjusted throughout childhood. The goal is to start with hypermetropia in childhood that will convert into emmetropia or mild myopia in adulthood.

Child↗
PubMed2003

Postural stability in the elderly during sensory perturbations and dual tasking: the influence of refractive blur.

PURPOSE: To determine the influence of refractive blur on postural stability during somatosensory and vestibular system perturbation and dual tasking. METHODS: Fifteen healthy, elderly subjects (mean age, 71 +/- 5 years), who had no history of falls and had normal vision, were recruited. Postural stability during standing was assessed using a force platform, and was determined as the root mean square (RMS) of the center of pressure (COP) signal in the anterior-posterior (A-P) and medial-lateral directions collected over a 30-second period. Data were collected under normal standing conditions and with somatosensory and vestibular system perturbations. Measurements were repeated with an additional physical and/or cognitive task. Postural stability was measured under conditions of binocular refractive blur of 0, 1, 2, 4, and 8 D and with eyes closed. The data were analyzed with a population-averaged linear model. RESULTS: The greatest increases in postural instability were due to disruptions of the somatosensory and vestibular systems. Increasing refractive blur caused increasing postural instability, and its effect was greater when the input from the other sensory systems was disrupted. Performing an additional cognitive and physical task increased A-P RMS COP further. All these detrimental effects on postural stability were cumulative. CONCLUSIONS: The findings highlight the multifactorial nature of postural stability and indicate why the elderly, many of whom have poor vision and musculoskeletal and central nervous system degeneration, are at greater risk of falling. The findings also highlight that standing instability in both normal and perturbed conditions was significantly increased with refractive blur. Correcting visual impairment caused by uncorrected refractive error could be a useful intervention strategy to help prevent falls and fall-related injuries in the elderly.

Aged↗
PubMed2003

Postural stability changes in the elderly with cataract simulation and refractive blur.

PURPOSE: To determine the influence of cataractous and refractive blur on postural stability and limb-load asymmetry (LLA) and to establish how postural stability changes with the spatial frequency and contrast of the visual stimulus. METHODS: Thirteen elderly subjects (mean age, 70.76 +/- 4.14 [SD] years) with no history of falls and normal vision were recruited. Postural stability was determined as the root mean square [RMS] of the center of pressure (COP) signal in the anterior-posterior (A-P) and medial-lateral directions and LLA was determined as the ratio of the average body weight placed on the more-loaded limb to the less-loaded limb, recorded during a 30-second period. Data were collected under normal standing conditions and with somatosensory system input disrupted. Measurements were repeated with four visual targets with high (8 cyc/deg) or low (2 cyc/deg) spatial frequency and high (Weber contrast, approximately 95%) or low (Weber contrast, approximately 25%) contrast. Postural stability was measured under conditions of binocular refractive blur of 0, 1, 2, 4, and 8 D and with cataract simulation. The data were analyzed in a population-averaged linear model. RESULTS: The cataract simulation caused significant increases in postural instability equivalent to that caused by 8-D blur conditions, and its effect was greater when the input from the somatosensory system was disrupted. High spatial frequency targets increased postural instability. Refractive blur, cataract simulation, or eye closure had no effect on LLA. CONCLUSIONS: Findings indicate that cataractous and refractive blur increase postural instability, and show why the elderly, many of whom have poor vision along with musculoskeletal and central nervous system degeneration, are at greater risk of falling. Findings also highlight that changes in contrast sensitivity rather than resolution changes are responsible for increasing postural instability. Providing low spatial frequency information in certain environments may be useful in maintaining postural stability. Correcting visual impairment caused by uncorrected refractive error and cataracts could be a useful intervention strategy to help prevent falls and fall-related injuries in the elderly.

Aged↗
PubMed2001

Does neonatal ocular misalignment predict later abnormality?

PURPOSE: A longitudinal prospective study was carried out to ascertain the significance of neonatal ocular misalignments. METHODS: Pre-school vision screening and hospital records were examined to determine the visual outcome of 1150 infants classified into 'often' (> 15% of waking hours), 'occasionally' (< 15%) or 'never' having an ocular misalignment (neonatal squint) in the first 8 weeks of life. Chi2 and Fisher's exact tests and ANOVA were used to analyse the data. RESULTS: When compared with infants who had squinted occasionally or never, frequent squinting in the neonatal period (which occurred in 7.7% of the subjects) was significantly associated with having been prescribed spectacles (p = 0.04), both for hypermetropia (p = 0.04) and for myopia (p = 0.05). Frequent squinters also had a higher incidence of significant esodeviation (p = 0.04) and were more likely to be > 21 days premature (p = 0.05). Small numbers of abnormalities made statistical analysis limited, but there were weak trends towards more myopic and oblique astigmatism in the 'never' group. The esotropias in the 'often' group were more frequently intermittent than those found in the other groups. CONCLUSIONS: Occasional squinting in the first 8 weeks of life appears to be normal neonatal behaviour. Frequent squinting trebles the chances of developing a significant esodeviation or refractive error severe enough to require spectacles before 5 years of age but incidence of abnormality still does not exceed 9%.

Analysis of Variance↗
PubMed1988

Ophthalmology in mentally retarded adults. A clinical survey.

Examination of 228 mentally retarded adults revealed that every fourth person in the group had a considerable visual handicap. In some of these cases this handicap was previously unknown. More than half of the examined had one or more ocular disorders. In 12 cases there was need for surgery. Fourteen eyes have subsequently been operated on, all without complications. Eight of these operations resulted in improved vision. Considerable refractive errors were found in 54 of the examined. In 70 cases glasses were prescribed, and in a majority of these cases the glasses were worn.

Adult↗
PubMed1996

Reduced accommodation in children with cerebral palsy.

Accommodation in 43 subjects with cerebral palsy was measured objectively using a dynamic retinoscopy technique, which has already been shown to be reliable and repeatable. The subject's ages ranged from 3 to 35 years. Of these, 42% were found to have an accommodative response pattern which was different from the normal control group for his/her age. Nearly 29% had an estimated amplitude of accommodation of 4 D or less. The presence of reduced accommodation was found to be associated with reduced visual acuity, but was not associated with cognitive or communication ability, refractive error or age. The prevalence of other ocular disorders in this group is also high. These findings have developmental and educational implications.

Accommodation, Ocular↗
PubMed1996

Morning-to-evening change in refraction, corneal curvature, and visual acuity 11 years after radial keratotomy in the prospective evaluation of radial keratotomy study. The PERK Study Group.

PURPOSE: Previous reports demonstrate morning-to-evening changes in ophthalmic measurements at 3 months, 1 year, and 4 years after radial keratotomy. The authors determine whether diurnal change in refractive error persists 11 years after radial keratotomy surgery in the Prospective Evaluation of Radial Keratotomy (PERK) study. METHODS: Seventy-one patients were examined in the morning and evening a mean of 11.1 +/- 0.6 years (range, 10-12.7 years) after undergoing radial keratotomy under a standardized protocol using a diamond blade. RESULTS: Between the morning and evening examinations, the mean change in the spherical equivalent of refraction was a 0.31 +/- 0.58-diopter (D) increase in minus power in first eyes. Thirty-six (51%) eyes had an increase in minus power of the manifest refraction of 0.50 to 1.62 D; 22 (31%) had a change in refractive cylinder power of 0.50 to 1.25 D; 9 (13%) had a decrease in uncorrected visual acuity of two to seven Snellen lines; and 25 (35%) showed central corneal steepening measured by keratometry of 0.50 to 1.94 D. Two (3%) eyes lost two lines of spectacle-corrected visual acuity, whereas one (1%) eye gained two lines. In patients whose both eyes underwent surgery, a high degree of symmetry was observed in morning-to-evening refractive change. CONCLUSION: In some patients after radial keratotomy, morning-to-evening change of refraction and visual acuity persists for at least 11 years, although in most patients the magnitude of this change is small. Thus, diurnal fluctuation may be a permanent sequela of radial keratotomy in some individuals.

Circadian Rhythm↗
PubMed2004

Congenital disorders of the optic nerve: excavations and hypoplasia.

The principal congenital abnormalities of the optic disc that can significantly impair visual function are excavation of the optic disc and optic nerve hypoplasia. The excavated optic disc abnormalities comprise optic disc coloboma, morning glory syndrome, and peripapillary staphyloma. Optic nerve hypoplasia manifests as a small optic nerve, which may or may not be accompanied by a peripapillary ring (the double ring sign). In addition, the optic disc cupping, which occurs as a sequel to some cases of periventricular leucomalacia, can arguably be classified as a type of optic nerve hypoplasia. All of these conditions can be unilateral or bilateral and can impair visual function mildly or severely. It is essential that children with poor vision due to any of these conditions are managed by treating refractive errors, giving occlusion therapy in selected cases, and optimising the conditions at home and at school in an attempt to ensure that impaired vision does not impede development or education.

Child, Preschool↗
PubMed1988

Requirements and characteristics of 500 consecutive patients consulting an ophthalmic medical practitioner.

This paper reports the results of a prospective survey on 500 consecutive patients consulting an ophthalmic medical practitioner. The reason for consultation, and results of refraction and examination were analysed. The majority required only a refraction. One in 8 visits was for primary ophthalmic health care other than refraction. An abnormality of the visual system (other than refractive error) was present in 19% of patients. Five per cent required referral to their general practitioner.

Adolescent↗
PubMed1985

The relation of astigmatism and hyperopia (more effective plus).

Two-hundred and ninety eight high astigmatic refractive errors are reviewed in order to establish the clinical and theoretical relationship of high astigmatism to hyperopia. All methods of analysis demonstrated that high astigmatism and greater plus power are related.

Adolescent↗
PubMed2006

Ophthalmic findings in apert syndrome prior to craniofacial surgery.

PURPOSE: To determine ophthalmic findings in patients with Apert syndrome before craniofacial surgery. DESIGN: A cross-sectional retrospective study. METHODS: Review of 63 cases (27 males, 36 females) with Apert syndrome without craniofacial surgery from the Australian Craniofacial Unit. Demographic data, age of presentation, and ophthalmic findings at the first presentation were recorded. RESULTS: At a mean age of four years and median age of one year, at least 14% of patients had amblyopia, 60% of patients had strabismus, 19% of patients had anisometropia, and 34% of eyes had ametropia. Exposure keratopathy and corneal scarring occurred in at least 13% of patients and optic atrophy in at least 8% of patients. CONCLUSIONS: This study demonstrated that patients with Apert syndrome were at risk of amblyopia because of high prevalence of refractive errors, strabismus, and anisometropia. Exposure keratopathy and corneal scarring occurred commonly.

Acrocephalosyndactylia↗
PubMedDate not supplied

Evaluation of a hand-held autorefractor in children younger than 6.

PURPOSE: To evaluate a hand-held portable autorefractor in a pediatric population and compare results with those found on retinoscopy by experienced pediatric retinoscopists. METHODS: One-hundred and two children aged 5 to 72 months were examined with and without cycloplegia using an autorefractor, and the results compared with those found on standard retinoscopy by two ophthalmologists masked as to the autorefractor findings. Results were converted from conventional notation using plus cylinder to the h-space notation and compared in three-dimensional h-space. RESULTS: There was remarkable agreement between the results found by autorefraction and manual retinoscopy using loose lenses or a phoropter. The findings were similar both for sphere and cylinder across the age ranges studied. CONCLUSIONS: The Nikon Retinomax is an accurate instrument to estimate refractive error in children younger than 6 and could prove useful in the office, the operating room, or as a screening device.

Child↗
PubMed2006

Impact of impaired vision and eye disease on quality of life in Andhra Pradesh.

PURPOSE: To determine the impact of visual impairment and eye diseases on quality of life (QOL) in an older population of Andhra Pradesh in southern India. METHODS: The World Health Organization (WHO) QOL (WHOQOL) instrument was adapted as a health-related quality of life (HRQOL) instrument for administration to adults participating in the Andhra Pradesh Eye Disease Study. Participants aged 40 years and older (n = 3702), 99.4% of the 3723 eligible, who underwent interview and detailed dilated ocular eye evaluation by trained professionals were included in this study. Psychometric properties of the HRQOL instrument were evaluated among visually impaired people. Relationships among overall QOL scores and presenting visual acuity in the better eye, specific eye diseases, and demographic variables were examined. RESULTS: Internal consistency was high for the entire questionnaire (alpha = 0.94). Each item of the QOL scale had an adequate item-total correlation (range, 0.25-0.77) greater than 0.2. After adjusting for demographic variables and ocular disease, Subjects with blindness had significantly lower QOL scores. Subjects with glaucoma or corneal disease independent of visual acuity had lower scores than subjects without those eye diseases. Subjects with cataract or retinal disease had significantly lower scores than those without cataract or retinal disease in the model without visual acuity but not when visual acuity was added to the model. CONCLUSIONS: Decreased QOL was associated with the presence of glaucoma or corneal disease independent of visual acuity and with cataract or retinal disease as a function of visual acuity. Visual impairment from uncorrected refractive errors was not associated with decreased QOL.

Adult↗
PubMed1977

Down's syndrome: a ten-year group study.

Thirty individuals with the clinical diagnosis of Down's syndrome received ophthalmologic examination periodically over 10 years at a state school for exceptional children. External examination, retinoscopy, anterior segment evaluation, ophthalmoscopy, and tonometry were usually done. The ages at present range from 10 to 50 years. The sex ratio was 80% male and 20% female. Three subjects died during the course of the study. The most frequent ocular anomalies were oblique fissures, refractive error, blepharoconjunctivitis, epicanthus, and Brushfield's spots. All of these occurred in 50% or more of the subjects.

Adolescent↗
PubMed2001

Clinical evaluation of the Shin-Nippon SRW-5000 autorefractor in adults.

A clinical evaluation of the Shin-Nippon SRW-5000 (Japan), a newly released commercial autorefractor, was undertaken to assess its repeatability and validity compared to subjective refraction. Measurements of refractive error were performed on 200 eyes of 100 subjects (aged 24.4 +/- 8.0 years) subjectively (non-cycloplegic) by one optometrist and objectively with the SRW-5000 autorefractor by a second. Repeatability was assessed by examining the differences between the seven autorefractor readings taken from each eye and by re-measuring the objective prescription of 50 eyes at a subsequent session. Although the SRW-5000 read slightly more plus than subjective refraction (mean spherical equivalent +0.16 +/- 0.44 D), it was found to be highly valid (accurate) compared to subjective refraction and repeatable over the prescription range of +6.50 to -15.00 D examined. The Shin-Nippon SRW-5000 autorefractor is therefore a valuable complement to subjective refraction and as it offers the advantage of a binocular open field-of-view, has a great potential benefit for accommodation research studies.

Adolescent↗