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PubMed2002

Effects of optical defocus and spatial contrast on anterior chamber depth in chicks.

The goal of this study was to investigate the effect of optical defocus and spatial contrast on refractive development and, in particular,on anterior chamber growth. Ninety chicks were raised from day 4-10 post-hatching wearing monocular lenses (+/-10 Dor 0 D), in an environment with either high, low or no spatial contrast patterns: 30%, 6% or 0% contrast, respectively. At day 10, the chicks' refractive state and ocular components were assessed using retinoscopy and A-scan ultrasonography. Ocular defocus resulted in sign-dependent significant differences in refractive error, axial length and vitreous chamber depth. Lens wear also led to significant spatial contrast dependent changes in anterior chamber depth. Varying ambient spatial contrast in the chick's environment did not inhibit emmetropization processes; however, anterior chamber growth was particularly susceptible to changes in spatial contrast.

Animals↗
PubMed1990

The use of spectacles in the treatment of congenital esotropia and amblyopia--a financial hazard.

Congenital esotropia and amblyopia are treated during the 'sensitive period' of brain-eye development. Not all children require spectacles for treatment of these conditions but when refractive errors are present, correct and properly fitting spectacles play an important part. This prospective survey shows that one-third of the under three-year-old children wearing spectacles require surgery for esotropia, and that one-third of all children under eight years of age wearing spectacles need amblyopia treatment. It is uninterrupted treatment in these age groups that produce results. Approximately 50% of children wearing spectacles in the four-year-old and under group need a second or third pair of spectacles within a 12-month period. If these spectacles become unsuitable because of dense scratches, changed refraction or poor fit because of increasing P D, then the treatment is interrupted and the visual acuity is likely to regress. Many families cannot afford a second or third pair of spectacles within the 12-month period and hospital benefit funds often will not help. The treatment is interrupted. This financial hazard must be overcome.

Amblyopia↗
PubMed1980

Characteristics of infantile esotropia following early bimedial rectus recession.

A homogeneous group of infantile esotropes were studied who underwent surgical alignment before 1 year of age. Three groups emerged: those who remained stable following their initial early alignment, those who were well aligned and remained stable for prolonged periods of time and then decompensated, and those who were unstable throughout the observation period. Preoperatively, no factors were identified that predicted into which group each patient might enter. Other associated factors were identified that affected the strabismic angle and these were overactions of the inferior oblique muscles, dissociative vertical deviation, rotary and other forms of nystagmus, amblyopia, and changing refractive errors. The treatment modalities consisted of miotics, glasses, bifocals, occlusion, and repeated operations. This study underscores the instability of the conditions of patients with infantile esotropia and the need for repeated observations throughout the first decade of life.

Amblyopia↗
PubMed1986

Congenital upper lid coloboma.

Twenty-two patients with congenital upper lid colobomas were assessed. Strabismus occurred in 13 cases and was associated with bands of fibrous tissue or adhesions, high refractive errors and opacities in the ocular media. A traction test is strongly recommended early in all children with congenital upper lid colobomas. A lateral cantholysis and direct closure was the commonest type of surgery, but unless the coloboma closed easily a lower lid rotation flap gave the best results.

Adolescent↗
PubMed2005

Functional and anatomic outcome of scleral buckling versus primary vitrectomy in pseudophakic retinal detachment.

PURPOSE: To conduct a randomized prospective clinical trial to compare primary vitrectomy without scleral buckling versus conventional scleral buckling surgery in pseudophakic primary retinal detachment (PPRD) in terms of anatomic attachment rate, functional outcome and complications. METHODS: Fifty consecutive eyes of 50 patients with PPRD were randomized into two groups, with 25 patients in each of group 1 (scleral buckling group) and group 2 (pars plana vitrectomy without buckling group) in a hospital setting and followed up at 1 week, 2 weeks, 6 weeks and 6 months. RESULTS: A primary reattachment rate of 76% (19 retinas) was obtained in group 1, while a reattachment rate of 84% (21 retinas) was achieved in group 2. The final anatomic reattachment rate was 100% in both groups. The causes of failure in group 1 were proliferative vitreoretinopathy in five eyes and open break/missed break in one eye. The causes of failure in group 2 were missed break/open break in three eyes and proliferative vitreoretinopathy in one eye. Best corrected visual acuity (BCVA) at 2 weeks was better in group 1, while the final BCVA at end of 6 months was two lines better in group 2. The mean change in refractive error was -- 1.38 D in group 1 and -- 0.85 D in group 2. CONCLUSIONS: Pars plana vitrectomy without buckling provides an effective treatment for PPRD and results in better longterm visual and anatomic outcomes than conventional scleral buckling.

Adult↗
PubMed1994

Ocular manifestations of Sotos syndrome.

BACKGROUND: Sotos syndrome (cerebral gigantism) is a congenital syndrome characterized by large body size for patient age, advanced bone age, and unusual facial characteristics with varying levels of cognitive, developmental and perceptual deficits. While more than 150 cases have been reported, only a single case report has been published in the ophthalmic literature. This study briefly reviews the pertinent aspects of this syndrome and reports on the medical, physical, developmental and ocular manifestations of 32 subjects. METHODS: Our patient population was obtained from several schools and colleges of optometry and private offices and clinics of optometrists and ophthalmologists. The Sotos Syndrome Support Association assisted in obtaining patients for this study as well. All children had been previously diagnosed as having SS. Commonly accepted methods for evaluating young, non-verbal, and/or handicapped children were used. RESULTS: Our findings indicate that moderate to high refractive error (hyperopia), nystagmus, and strabismus (esotropia) are commonly associated conditions of this syndrome. CONCLUSIONS: Since many of our subjects exhibited these amblyogenic precursors, a routine optometric vision evaluation should be an essential part of the individual educational and habilitation plan for all children with Sotos syndrome.

Abnormalities, Multiple↗
PubMed2006

The multi-ethnic pediatric eye disease study: design and methods.

PURPOSE: To summarize the study design of the Multi-Ethnic Pediatric Eye Disease Study (MEPEDS). METHODS: The objectives of the MEPEDS are to: (1) estimate age- and ethnicity-specific prevalence of strabismus, amblyopia, and refractive error; (2) evaluate the association of selected risk factors with these ocular disorders; and (3) evaluate the association of ocular conditions on limitations in health-related functional status in a population-based sample of 12,000 children aged 6-72 months from four ethnic groups--African-American, Asian-American, Hispanics/Latinos and non-Hispanic White. Each eligible child undergoes an eye examination, which includes an interview with his/her parent. The interview includes an assessment of demographic, behavioral, biological, and ocular risk factors and health-related functional status. The examination includes fixation preference testing, visual acuity, stereoacuity, axial length measurement, cycloplegic refraction, keratometry, eye alignment, and anterior and posterior segment examination.

Amblyopia↗
PubMed2001

Refractive development in children with Down's syndrome: a population based, longitudinal study.

AIMS: To study the refractive development in children with Down's syndrome longitudinally. METHODS: An unselected population of 60 children with Down's syndrome was followed with repeated retinoscopies in cycloplegia for 2 years or more (follow up 55 (SD 23) months). Accommodation was assessed with dynamic retinoscopy. RESULTS: From longitudinal spherical equivalent values of the right eye, three main categories of refraction were defined: stable hypermetropia (<1.5 D difference between the first and last visit) (n=34), increasing hypermetropia ("hypermetropic shift"; >/=1.5 D difference) (n=11), and decreasing hypermetropia/development of myopia ("myopic shift"; >/=1.5 D difference) (n=9). Patients with anisometropia (n=6) were evaluated separately. In the stable hypermetropia group three sublevels were chosen: low (</=+2.0 D at the last visit), moderate (+2.25 to + 4.0 D), and high (>+4.0 D). An accommodation weakness was found in 55% of the children. Accommodation weakness was significantly less frequent in the stable, low grade hypermetropia group (22%) than in all the other groups (p=0.008). The frequency of astigmatism >/=1.0 D at the last visit was 57%, the direction of axis being predominantly "with the rule." All the eyes with oblique astigmatism had a side specific direction of axis; the right eyes belonging to the 135 degrees axis group and the left eyes to the 45 degrees axis group. CONCLUSION: A stable, low grade hypermetropia was significantly correlated with a normal accommodation. Accommodation weakness may be of aetiological importance to the high frequency of refractive errors encountered in patients with Down's syndrome. A striking right-left specificity in the oblique astigmatic eyes suggests that mechanical factors on the cornea from the upward slanting palpebral fissures may be a major aetiological factor in the astigmatism.

Accommodation, Ocular↗
PubMedDate not supplied

Can congenital nasolacrimal-duct obstruction interfere with visual development? A cohort case control study.

PURPOSE: To ascertain if tear film disturbance in congenital nasolacrimal-duct obstruction (CNLDO) interferes with visual maturation. METHODS: Review of a cohort of children in which the occurrence and duration of CNLDO had been previously documented. Information obtained included acuity, refractive data, and presence or absence of strabismus. The incidence of abnormality in the CNLDO group was compared with that in controls, which were fellow eyes in those children with unilateral obstruction, and all children with no history of CNLDO. RESULTS: Of 4792 children, visual acuity data were obtained on 2249. There was no difference in the incidence of amblyopia in CNLDO children compared with controls (p < 0.89) nor in the watering eye compared with the fellow eye (p < 0.58). No correlation between refractive error or astigmatism and CNLDO (p < 0.26 and p < 0.32 respectively) was found. Strabismus was no more common in CNLDO than in controls (p < 0.89). CONCLUSIONS: This study found no evidence to suggest that visual maturation is adversely affected by allowing spontaneous resolution of CNLDO.

Amblyopia↗
PubMed2004

Visual impairment and ocular abnormalities in children with fetal alcohol syndrome.

Children with fetal alcohol syndrome (FAS) may have impaired vision and various ocular abnormalities. All parts of the eye may be affected and anomalies such as microphthalmus, microcornea, Peters' anomaly, cataract, persistent hyperplastic primary hyaloid vitreous body, coloboma of the iris and choroid, retinal dysplasia and, most commonly, optic nerve hypoplasia and tortuosity of the retinal vessels, have been reported. The periocular facial features consist of short palpebral fissures (included in the criteria for diagnosis of FAS), telecanthus, epicanthus and blepharoptosis. Visual function may be reduced to a moderate or severe degree. Refractive errors and strabismus are common. Considering the high frequency of ocular pathology in FAS, an ophthalmological examination is helpful in making the diagnosis. The early detection of impaired vision and ocular abnormalities in affected children is important in the management of the disorder. In this article, the ophthalmological signs and symptoms in children with FAS are presented.

Child↗
PubMed1990

Review of ophthalmic factors in dyslexia.

Dyslexia and the effect of visual problems on reading ability have long been subjects of controversy. This paper critically reviews the literature on the relationship between reading disability and visual acuity, refractive error, binocular vision anomalies, eye movements, ocular pathology and the transient and sustained visual systems. The limitations of much of the work in this field are described, with particular reference to the problems of subject selection and group matching. Tentative conclusions, with deference to the complex nature of dyslexia, are drawn and suggestions are made for future research.

Accommodation, Ocular↗
PubMed1999

Abnormal tear dynamics and symptoms of eyestrain in operators of visual display terminals.

OBJECTIVES: To clarify the relation between the prevalence of dry eye syndrome and subjective symptoms of asthenopia in visual display terminal (VDT) operators. METHOD: 722 VDT workers (242 subject workers with symptoms of asthenopia and 480 controls without such symptoms) without obvious organic ocular diseases received an ophthalmological examination consisting of refractometry and a tear function (phenol red thread) test. RESULTS: More than 30% of symptomatic workers were found to meet the criteria of dry eye, and the odds ratio compared with the controls was 4.61 (p < 0.001). This odds ratio was significantly greater than that obtained for refractive errors (2.31). CONCLUSIONS: Although this cross sectional study could not prove that dry eyes are the cause of asthenopia, the profound association of dry eyes with symptoms of asthenopia could be verified. It would be useful to carry out tear function tests in workers with symptoms of asthenopia.

Adult↗
PubMed1998

A new school-based program to provide eyeglasses: childsight.

OBJECTIVE: To address the unmet need for glasses encountered in an urban school setting by developing and implementing a school-based, cost-effective program that provides appropriate spectacle correction to needy children. METHODS: A total of 5851 students 9 to 15 years of age in 4 middle schools in northern Manhattan were screened for vision. Those with vision worse than 20/40 were examined, given glasses if appropriate, or referred for additional evaluation. RESULTS: Of the 5851 children screened, 1614 (28%) had a failing result, with visual acuity less than 20/40 in the worse eye. Of this group, 1082 were given glasses that were assembled at the school within 1 hour of testing. Ten percent of the group that required glasses already had them, and the remaining were referred for a complete ophthalmic examination that was completed in 58 cases. Only 14 of these had vision loss unrelated to refractive error. CONCLUSIONS: The program successfully treated 88.3% of the children within the school who needed glasses. Given that only 10% of children who needed glasses had them, it indicates a huge need to provide glasses to at least a million children in this age group in the United States.

Adolescent↗
PubMed1994

Tonic accommodation: a review. II. Accommodative adaptation and clinical aspects.

Part I of this review considered basic aspects of tonic accommodation (TA), i.e. the accommodative response observed under degraded stimulus conditions. Part II considers accommodative adaptation, i.e. the apparent change in TA following periods of sustained fixation, and clinical aspects of both baseline TA and accommodative adaptation. It is suggested that the apparent post-task shift in TA reflects the slow rate of decay of the stimulus-mediated adaptive accommodative response, while the actual level of tonic innervation to the ciliary muscle remains relatively constant. The clinical implications of both TA and accommodative adaptation are discussed with regard to night, space and instrument myopia and refractive error development, notably nearwork-induced myopia. It is concluded that the evidence for any association between this form of myopia and either TA or accommodative adaptation is equivocal, and furthermore it seems likely that TA plays only a minor role in influencing the closed-loop steady-state accommodative response.

Accommodation, Ocular↗
PubMed2005

Long-term visual pathology in children with significant perinatal complications.

Eye research in infants who experience significant perinatal complications has been restricted to evaluation of structural ocular disease and spatial vision, and results show that these aspects of vision are at increased risk for abnormal or delayed development. To expand upon previous work, a battery of 17 vision tests was employed to assess, comprehensively, long-term outcome of functional vision. Seventy-six children (38 males, 38 females), between the corrected ages of 2 years 11 months and 10 years 2 months (mean 6y 6mo) with various significant complications (e.g. very preterm birth, bronchopulmonary dysplasia, intraventricular hemorrhage) were compared to normally developing, age-matched control children (n = 61; mean age 7y 1mo) on measures of visual acuity, contrast sensitivity, stereoacuity, peripheral vision, color vision, astigmatism, and binocular alignment. Results showed that at-risk children had more test results that fell within the suspect or abnormal range. At-risk children also had a slightly higher incidence of ocular disorders (e.g. strabismus) and refractive error. These data imply that children who experienced significant perinatal risk factors are at risk for long-term deficits of functional vision. However, most of these deficits appear to be relatively mild.

Bronchopulmonary Dysplasia↗
PubMed1992

A prospective study of ocular abnormalities in hearing impaired and deaf students.

In a prospective study of 505 hearing impaired and deaf students conducted at Children's Hospital Eye Clinic, 48.7% were found to have significant ocular abnormalities. The prevalence of myopia, astigmatism, and pathological intraocular changes was found to be significantly increased over the general population. In addition, the prevalence of ocular abnormalities generally increased with the severity of the hearing loss. Of importance was the high prevalence of rubella-consistent abnormalities in the hearing impaired and deaf student populations. Rubella syndrome may be responsible for a major portion of high refractive errors and ocular pathological changes. It is recommended that ENT specialists and pediatricians be aware of the nearly 50% chance of ocular abnormality in hearing impaired and deaf students, and that ophthalmologic examination may be valuable for identification or confirmation of the etiology of hearing impairment.

Adolescent↗
PubMed2005

[Ophthalmology].

The Headache Classification Subcommittee of the International Headache Society classifies headaches related to eyes as "Headache attributed to disorder of eyes" in the International Classification of Headache Disorders; 2nd Edition(ICHD-II). It consists of "Headache attributed to acute glaucoma", "Headache attributed to refractive errors", "Headache attributed to heterophoria or heterotropia(latent or manifest squint)", "Headache attributed to ocular inflammatory disorder". But other causes of headache related to eyes exist. For example, dry eye causes the headache. This article mentions to "Headache attributed to disorder of eyes" in ICHD-II, and additionally, describes other causes of headache associated with disease of eye.

Acute Disease↗
PubMedDate not supplied

The use of orthoptics in dyslexia.

In 73 children with reading difficulty, ophthalmological evaluation showed that 18 had overt refractive errors, 18 had dyslexia and no ocular anomalies, and 37 had impaired fusional amplitudes, 24 of whom were dyslexic. In all patients with poor fusional amplitudes the reading mechanism could be improved with orthoptic exercises designed to augment the fusional amplitudes. The treatment did not affect the perceptual defect associated with dyslexia.

Adolescent↗

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