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1.
PURPOSE: To determine the causes of visual impairment in a population-based group of visually impaired preterm children. METHODS: Ophthalmological examination and magnetic resonance imaging or computed tomography of the brain were performed in all visually impaired preterm children born 1989-95 in V?rmland. RESULTS: Ten of 18 children had periventricular leukomalacia affecting the optic radiation, six had other lesions or malformations in the posterior visual pathways/cortex, but no child had visually impairing retinopathy of prematurity. CONCLUSION: We conclude that cerebral lesions or malformations are common causes of the visual functional deficit in visually impaired children born preterm. Brain damage should be suspected in a prematurely born child who presents with either of the signs: fixation difficulties, strabismus or nystagmus.  相似文献   

2.
This study evaluates functional vision in visually impaired children with stage IV to V cicatricial retinopathy of prematurity (CROP) by comparing results derived from the Teller acuity cards and a battery of behavioral tasks, the visual function battery (VFB). Vision was evaluated in 26 eyes of 15 children ages 6 months to 14 years, who underwent retinal reattachment procedures for active stage IV and stage V retinopathy of prematurity. Results showed that 10 of 26 eyes (38%) had a recordable grating acuity to Teller acuity card assessment. Twenty-five of 26 eyes (96%) showed a response to the VFB. Sixteen of 26 eyes (62%) showed recordable scores with the VFB but no corresponding scores with the Teller acuity cards. The VFB may be more reliable than the Teller acuity cards in measuring visual function in the very low acuity range.  相似文献   

3.
OBJECTIVES: 1. To ascertain the causes of severe visual impairment and blindness in children in schools for the blind in South Africa. 2. To determine the major avoidable causes. 3. To determine causation by ethnic group. DESIGN: A cross-sectional survey, undertaken at 15 of the 16 schools for the blind in South Africa, during May-September 1996, using standard WHO methodology. SUBJECTS: Children less than 16 years of age on May 1996. RESULTS: Of 1,615 eligible children, 1,311 were examined. According to WHO categories of visual impairment, using the corrected visual acuity in the better eye, 30.4% of children were blind (< 3/60, BL), 12.6% had severe visual impairment (< 6/60-3/60, SVI), 42.3% were visually impaired (< 6/18-6/60), and 12.0% had no impairment (6/18 or better). The anatomical sites of SVI/BL in 564 children were: retina 38.5%; optic nerve 15.2%; cornea/phthisis bulbi 11.0% and glaucoma 6.7%. Aetiological categories of SVI/BL were: hereditary diseases 33.0%; intra-uterine factors 0.9%; perinatal conditions 13.1%; acquired conditions of childhood 11.5%. In 41.5% the underlying cause could not be determined. In 38.8% of children with SVI/BL the cause was avoidable, i.e. preventable or treatable. The main causes varied between ethnic groups, the major difference being the higher proportion of retinopathy of prematurity in white and Indian children. CONCLUSIONS: The study suggests that 38.8% of causes of SVI or blindness in children in schools for the blind in South Africa are avoidable, and that specific control measures need to be targeted at different ethnic groups.  相似文献   

4.
AIMS: Visual outcome of 66 eyes in 37 patients who had undergone treatment with either cryotherapy or diode laser for threshold retinopathy of prematurity was assessed. METHODS: 17 patients, representing 30 eyes treated with cryotherapy, were examined at between 56 and 98 months corrected age (median 68 months). 20 patients representing 36 eyes treated with diode laser, were examined at between 30 and 66 months corrected age (median 51 months). Structural outcome was categorised as: optimal--flat posterior pole; suboptimal--macular ectopia, optic nerve hypoplasia, retinal fold involving the macula, and retinal detachment involving the macula. RESULTS: Optimal structural outcome was, in the absence of amblyopia, associated with optimal visual acuity (of 6/12 or better) in all cases, with most eyes achieving a visual acuity of 6/9 or 6/6. Suboptimal structural outcome was invariably associated with suboptimal visual acuity. Amblyopia was present in eight out of 20 cryotherapy treated eyes and in five out of 26 laser treated eyes with an optimal structural outcome. Refractive errors were significantly less in laser treated eyes as was the incidence of anisometropic amblyopia. CONCLUSION: Eyes treated with either cryotherapy or diode laser for threshold retinopathy of prematurity with optimal structural outcome are associated with development of optimal visual acuity--that is, 6/12 or better. Treatment with either cryotherapy or laser does not in itself reduce the visual potential of these eyes.  相似文献   

5.
PURPOSE: To evaluate the involvement of central visual pathways in cases of periventricular leukomalacia, and to correlate the neuroradiologic findings with the degree of visual acuity. METHODS: The MR brain examinations of 27 preterm children affected by cerebral palsy resulting from periventricular leukomalacia and without significant ophthalmologic lesions were reviewed retrospectively to search for possible involvement of the optic radiations and/or of the calcarine cortex. The data were compared with the degree of visual acuity estimated by means of the Teller Acuity Cards test. RESULTS: Seventeen (63%) of the 27 patients had cerebral visual impairment, which correlated strongly with MR lesions. Quantitative reduction and signal hyperintensity of the peritrigonal white matter and atrophy of the calcarine cortex were present in the more severe cases. In two blind patients, an altered MR signal was detected in the lateral geniculate bodies. CONCLUSION: This study clearly establishes a relationship between specific MR findings and visual impairment in children with periventricular leukomalacia. The finding of hyperintensity in the lateral geniculate bodies was interpreted as an axonal reaction. MR imaging is useful for detecting potential visual impairment and for improving clinical diagnosis.  相似文献   

6.
Various electrophysiological tests have been employed to reveal functional abnormalities at different levels of the visual system in insulin-dependent diabetic (IDDM) patients. The aim of our work was to assess, with a comprehensive neurophysiological protocol evaluating the retinal, macular and visual pathways functions, whether and when such electrophysiological abnormalities do appear in IDDM patients free of any fluorangiographic sign of retinopathy with various disease duration. Flash-electroretinogram (ERG), oscillatory potentials (OPs), pattern-electroretinogram (PERG), and visual evoked potentials (VEPs) in basal condition and after photostress were assessed in 12 control subjects (C) and 42 aged-matched IDDM patients without clinical retinopathy (DR-) divided, on the basis of the disease duration, into 4 groups (1-5, 6-10, 11-15, 16-20 years). In addition another age-matched group of IDDM patients with a background retinopathy (DR+; n = 12; duration of disease 18 +/- 49 years) was evaluated. In all IDDM DR-patients PERG and VEP were significantly impaired. In addition, groups 11-15 and 16-20 years displayed impaired OPs. All electrophysiological parameters were further impaired in DR+ patients. In conclusion, retinal, macular and visual pathways functions are differently impaired in IDDM (DR-) patients with different disease duration. Electrophysiological impairment starts in the nervous conduction of the visual pathways with an early involvement, goes on in the innermost retinal layers and in the macula and ends in the middle and outer retinal layers.  相似文献   

7.
BACKGROUND: Cryotherapy administered to eyes with severe acute-phase (threshold) retinopathy of prematurity benefits retinal structure and visual acuity compared with the natural course of the retinopathy. OBJECTIVES: To determine the extent of peripheral field abnormalities in eyes with threshold retinopathy of prematurity that had retinal structure preserved by cryotherapy. METHODS: Kinetic perimetry was performed with a Goldmann perimeter by masked testers on patients in whom bilateral threshold retinopathy of prematurity developed and who had been randomly assigned to undergo cryotherapy in one eye and no cryotherapy in the fellow eye. With the V-4-e and the II-4-e targets, eight meridians were tested: 0 degrees, 45 degrees, 90 degrees, 135 degrees, 180 degrees, 225 degrees, 270 degrees, and 315 degrees. The median value of three presentations in each meridian was accepted as the extent in that meridian. RESULTS: Fourteen eyes (eight treated and six control) of eight patients (mean age, 9.9 years; range, 6 to 11 years) had adequate vision to undergo fields testing. Mean (+/-SE) extent of visual field for treated vs control eyes was 36 degrees +/- 3 degrees vs 46 degrees +/- 6 degrees for the II-4-e target and 49 degrees +/- 4 degrees vs 59 degrees +/- 6 degrees for the V-4-e target. This difference was consistent across all eight meridians for either target, and repeated-measures analysis of variance showed that cryotherapy was associated with smaller visual field extent for both target sizes (P=.08). CONCLUSION: The results of this small pilot study suggest that eyes that have retinal structure and acuity preserved by cryotherapy for severe acute-phase retinopathy of prematurity have slightly smaller visual fields than untreated eyes with severe acute-phase retinopathy of prematurity that had vision preserved.  相似文献   

8.
The study investigates the neurological substrate in children with congenital disorders of the peripheral visual system (CDPVS), i.e. disorders of the anterior visual pathways and the globe. The design is retrospective; brain MRI and/or CT scans were traced and reviewed for 79 of 254 children with CDPVS on our database. The neuroradiological findings were considered in the context of degree of visual impairment (profound [PVI] and severe [SVI]), developmental outcome (setback and non-setback), and mode of imaging (MRI and CT). Scans were abnormal in 40 of 79 (51%) children; 23 of 40 (58%) had more than one lesion; and in some children lesions not previously reported were found. The number of abnormalities per child was significantly higher in the PVI than the SVI group (P<0.05); the level of significance varied according to the method of scanning (MRI, P<0.001; CT, ns). Seven children were known to have had developmental setback; significantly more brain abnormalities per child were found in the group with setbacks than in the group without (P<0.001). Eighty-six percent (24 of 28) of MRI compared with 38% (22 of 58) of CT scans were abnormal. MRI detected more lesions per child than CT (P< 0.001). Thus, a significant amount of brain pathology occurs in children with CDPVS. The number of lesions varies directly with degree of visual impairment and both correlate with developmental outcome. As brain pathology will be only one of many factors influencing developmental progress in visually impaired children, prospective multifactorial studies of the CDPVS population, which include MRI studies of the neurological substrate, will be required to clarify the latter.  相似文献   

9.
Objective: To evaluate the construct validity of a tactile adaptation of the Wisconsin Card Sorting Test (TWCST) for use with individuals with visual impairment. Study Design: Static-group comparison (1-factor design with 3 levels). Setting: A VA Healthcare System residential rehabilitation center for persons with visual impairment. Participants: Fourteen persons who were both neurologically and visually impaired (NVI), 14 persons who were visually impaired but neurologically healthy (VI), and 15 healthy controls (HC). Measures: TWCST and Wechsler Adult Intelligence Scale (3rd ed.) Verbal scale (Psychological Corporation, 1997). Results: The TWCST accurately discriminated the NVI group from both the VI and HC samples. Conclusions: Findings provide preliminary support for the construct validity of the TWCST for use with persons with visual impairment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
BACKGROUND: Diabetic papillopathy is a benign unilateral or bilateral optic neuropathy with transient optic disk edema and minimal reduction in visual function. The optic disk edema typically resolves in a few months with no resulting optic atrophy and minimal or no decrease in acuity. The exact etiology of the disk edema is unknown, but theories include retinal vascular leakage into and surrounding the optic nerve and disruption of axoplasmic flow resulting from microvascular disease of the optic nerve head vasculature. CASE REPORTS: Two adult patients receiving insulin for type II diabetes mellitus manifested bilateral disk edema and minimal visual dysfunction. Both patients showed funduscopic evidence of mild-to-moderate nonproliferative diabetic retinopathy O.D. and O.S., and one patient had clinically significant macular edema in both eyes. The diagnosis in both cases was diabetic papillopathy. Both patients had significant resolution of their disk edema in 3 to 6 months, with stable acuities and no signs of optic atrophy. CONCLUSIONS: Although diabetic papillopathy is a well-known clinical entity in patients with type I diabetes, the clinical profile can be expanded to include individuals with type II diabetes.  相似文献   

11.
An ophthalmic follow-up comprised 88 children aged 7-10 years who had regular screening for retinopathy of prematurity (ROP) after their pre-term delivery 1982-84. Mean values of birth weight and gestational age in the 88 were 1467 g and 31 weeks. Out of 28 with early evidence of ROP four had progressed to bilateral blindness; the remaining 24 had at least a corrected visual acuity of 0.4 at disposal. The corrected median binocular acuity for all 88 was 0.95; however, the cumulated frequency curve was significantly below a previously stated norm in full-terms. The same conclusion was valid for single eye vision. Within the material, the visual score of the 28 with early ROP was significantly lower than in the remaining 60 subjects. Ophthalmoscopy often showed tortuosity of vessels, but no specific central retinal or optic nerve lesion to explain the slight general depression of visual acuity, and opacities of media contributed in only two subjects. It is concluded, that very preterm delivery generally influences the potential for developing full visual acuity, also in individuals without evidence of early ROP. Evidence of CNS-damage negatively influenced visual acuity score.  相似文献   

12.
PURPOSE: The authors present the "pattern" visual evoked potentials (VEP) analysis with use of the artificial neural networks (ANN). MATERIALS AND METHODS: The study involved 11 patients with compressive chiasmal optic neuropathy, 20 patients with optic neuritis, 12 patients with anterior ischaemic optic neuropathy, 20 patients with optic nerve atrophy from neuritis, 8 patients with demyelinative neuropathy, 5 patients with oedema optic nerve, 20 healthy persons. The tests of visual evoked potentials were performed with the use of computer system UTAS-E1000. Classification of potentials was made by correlation of outputs of ANN with results of confirmed neuro-ophthalmology conditions. RESULTS: ANN of different architecture were classified correctly in 80-100% of VEP record samples. CONCLUSIONS: The obtained correctness of classification confirms usefulness of VEP analysis as the objective diagnostic method in some neuro-ophthalmological diseases and indicates application of ANN in multifactor analysis.  相似文献   

13.
PURPOSE: To document that lacunar, atrophic lesions of the retinal pigment epithelium, previously reported as a complication of treatment, can result from the natural course of retinopathy of prematurity. METHODS: We reviewed photographs of patients diagnosed with retinopathy of prematurity at the Casey Eye Institute between 1979 and 1996. Lacunar atrophic lesions of the retinal pigment epithelium were correlated with the clinical records of the affected patients. RESULT: Three untreated eyes of three patients with retinopathy of prematurity had lacunar atrophic lesions of the retinal pigment epithelium. CONCLUSIONS: The spectrum of findings associated with untreated retinopathy of prematurity includes lacunar, atrophic lesions of the retinal pigment epithelium. These lesions are distinct from scars secondary to treatment and are possibly linked to macular dragging and exudative or serous retinal detachment.  相似文献   

14.
Three affected children from an inbred family had microcornea, microcephaly, congenital cataract, severe mental retardation, retinal dystrophy, optic nerve atrophy, hypothalamic hypogenitalism, and agenesis of the corpus callosum. The disorder is presumably autosomal recessive; no identical syndrome has been described, but we consider syndromes with similar features.  相似文献   

15.
BACKGROUND: Retinitis pigmentosa (RP) is one of the most common inherited retinal diseases, with a prevalence of about 1 in 3500 to 4500. Retinitis pigmentosa inversa is a rare variant of this disorder characterized by areas of choroidal degeneration with pigment migration and bony spicule formation in the macular area. In contrast to more typical forms of RP, this anomaly destroys central vision, leaving peripheral vision intact. CASE REPORT: A 47-year-old white male was followed for about 7 years with evidence of progressive retinal pigment epithelial atrophy and hyperpigmentation affecting both maculae. Since 1970, he had noted difficulty seeing at night as well as an acquired hearing deficit that appeared to be getting worse, ultimately impairing his ability to safely drive a truck. Medical history was positive for either chloroquine or hydroxychloroquine use for 2 to 3 years as malaria prophylaxis while he served in Vietnam. In addition, his father in Louisiana had visual loss of unknown cause. During the 7-year period, the condition progressed rapidly. The patient became virtually blind secondary to visual acuity loss with dense central and paracentral scotomas. The peripheral visual fields remained intact. After several years of extensive examinations, including laboratory, electroretinography, and genetic testing, a definitive diagnosis of RP inversa was made. DISCUSSION: RP inversa is a rare form of tapetoretinal degeneration that is characterized by decreased central vision with normal peripheral vision. A recessive form of inheritance has been postulated but never substantiated. Although there is currently no treatment, recent studies have indicated that 15,000 IU of vitamin A palmitate daily may slow the progression of retinitis pigmentosa; however, it is unknown whether this treatment would be effective for the inverse form of RP. Differential diagnoses include Leber's congenital amaurosis, central gyrate atrophy, central areolar choroidal sclerosis, progressive cone-rod dystrophy, syphilitic retinopathy, retinal toxicity from phenothiazine use, and chloroquine/hydroxychloroquine retinopathy.  相似文献   

16.
Chloroquine compounds are known to cause a retinopathy which typically begins in the central fundus giving rise to a "bull's eye" macula. Ultimately peripheral changes may become apparent. In the routine eye examination of such patients emphasis has been laid on the central area of the fundus. A case is presented where the retinopathy was not diagnosed until marked peripheral changes had occurred with peripheral pigment changes, attenuated retinal vessels, slight optic atrophy, peripheral visual field restriction and a subnormal electroretinogram. The typical "bull's eye" changes were not apparent. Routine examination of the peripheral fundus by means of ophthalmoscopy and perimetry is necessary to avoid missing any such retinopathy.  相似文献   

17.
BACKGROUND: Leber hereditary optic neuropathy (LHON) is a mitochondrial genetic disorder characterized by bilateral central visual loss typically in early adulthood. Few histopathologic studies, including ultrastructural and molecular genetic analysis, have been reported. METHODS: Ocular tissue was obtained postmortem from an 81-year-old woman with LHON from the Queensland 1 pedigree characterized by mutations at nucleotide positions 4160 and 14484. Routine histopathologic studies, electron microscopy, electron-probe analysis, and molecular genetic analysis were performed. RESULTS: Marked atrophy of the nerve fiber and retinal ganglion cell layers and optic nerves was present. Results of electron microscopic examination demonstrated 1.2 microns electron-dense, double-membrane-bound inclusions, consisting of calcium by electron-probe analysis, in retinal ganglion cells. The optic nerve was homoplasmic for mutations 4160 and 14484. CONCLUSION: Optic nerve and inner retinal atrophy in LHON may be a result of metabolic mitochondrial dysfunction leading to intramitochondrial calcification. Homoplasmy for mitochondrial mutations 4160 and 14484 in the leukocyte/platelet fraction of whole blood may correlate with homoplasmy in the optic nerve.  相似文献   

18.
PURPOSE: To report alterations of electrophysiologic tests, including the multifocal electroretinogram, in a case of acute zonal occult outer retinopathy. METHOD: We recorded photopic, scotopic, and single-flash electroretinograms and a multifocal electroretinogram in a 47-year-old woman with acute zonal occult outer retinopathy in the right eye. RESULTS: Her visual acuity was 20/20 in the right eye throughout the follow-up period. The electroretinograms indicated retinal impairment of the right eye, predominantly in the cones. The multifocal electroretinogram showed reduced responses corresponding to the visual field defect of the static perimetry. CONCLUSIONS: In acute zonal occult outer retinopathy, impairment of the retinal area results in a visual field defect. The multifocal electroretinogram can be useful in determining the location of the defect.  相似文献   

19.
Objective: The authors examined the interface between visual impairment and depressive symptoms on health behaviors, self-care, and social participation among adults ages 65 and older. Method: The authors analyzed data from the 1997–2004 National Health Interview Survey on visual impairment and depressive symptoms for 49,278 adults ages 65 and older, comparing visually impaired adults (n = 8,787) with and without depressive symptoms with a reference group of adults with neither condition (n = 3,136) for outcome measures: physical health, health behaviors, and difficulties with self-care and social participation. Results: Adults with visual impairment and severe depressive symptoms were more likely than adults with neither condition to smoke (14.9%, adjusted odds ratio [AOR] = 1.6), be obese (28.2%, AOR = 1.9), be physically inactive (80.5%, AOR = 3.0), have fair–poor health (76.0%, AOR = 26.5), and have difficulties with self-care (27.9%, AOR = 11.8) and social participation (52.1%, AOR = 10.9). Discussion and Conclusions: Older visually impaired adults with depressive symptoms are vulnerable to health decline and further disablement without timely interventions that target smoking cessation, healthy eating, and increased physical activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
BACKGROUND: Ischemic disorders of the retina and optic nerve head, which constitute a common cause of visual loss, are usually seen in patients with atherosclerosis. OBJECTIVE: To test the hypothesis that serotonin, which is released when platelets aggregate, may produce vasospasm in atherosclerotic monkeys and, thus, may contribute to the ischemic disorders and that short-term dietary treatment of atherosclerosis causes the propensity to vasospasm to subside. METHODS: We studied the response of retinal and posterior ciliary circulation to serotonin in 18 atherosclerotic (25 eyes) and 5 normal (8 eyes) cynomolgus monkeys. The eyes were evaluated by color fundus photography and fluorescein fundus angiography. The eyes were examined under basal conditions and, at a different time, during the intravenous infusion of serotonin. In 6 of the 18 atherosclerotic animals, the evaluation was repeated 5 to 12 months after discontinuing the atherogenic diet (ie, the regression group). RESULTS: Serotonin had no effect in normal monkeys. In 18 atherosclerotic monkeys, serotonin produced transient occlusion or delayed filling of the central retinal artery and/or posterior ciliary artery (PCA) in 9 eyes of 9 animals, involving the central retinal artery in 5, lateral PCA in 8, and medial PCA in 5, in various combinations. In 6 animals (6 eyes) of the regression group, the vasoconstrictor effect of serotonin was abolished completely, except in the medial PCA in 1 eye. CONCLUSIONS: Serotonin, in the presence of atherosclerotic lesions, can cause transient, complete occlusion or impaired blood flow in the central retinal artery and/or PCA. We speculate that this mechanism may play a role in the development of ischemic disorders of the retina and optic nerve head. Discontinuing the atherogenic diet abolished or markedly improved the serotonin-induced vasoconstriction within a few months.  相似文献   

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