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Retrospective analysis of refractive errors in children with vision impairment.

PURPOSE: Emmetropization is the reduction in neonatal refractive errors that occurs after birth. Ocular disease may affect this process. We aimed to determine the relative frequency of ocular conditions causing vision impairment in the pediatric population and characterize the refractive anomalies present. We also compared the causes of vision impairment in children today to those between 1974 and 1981. METHODS: Causes of vision impairment and refractive data of 872 children attending a pediatric low-vision clinic from 1985 to 2002 were retrospectively collated. As a result of associated impairments, refractive data were not available for 59 children. An analysis was made of the causes of vision impairment, the distribution of refractive errors in children with vision impairment, and the average type of refractive error for the most commonly seen conditions. RESULTS: We found that cortical or cerebral vision impairment (CVI) was the most common condition causing vision impairment, accounting for 27.6% of cases. This was followed by albinism (10.6%), retinopathy of prematurity (ROP; 7.0%), optic atrophy (6.2%), and optic nerve hypoplasia (5.3%). Vision impairment was associated with ametropia; fewer than 25% of the children had refractive errors < or = +/-1 D. The refractive error frequency plots (for 0 to 2-, 6 to 8-, and 12 to 14-year age bands) had a Gaussian distribution indicating that the emmetropization process was abnormal. The mean spherical equivalent refractive error of the children (n = 813) was +0.78 +/- 6.00 D with 0.94 +/- 1.24 D of astigmatism and 0.92 +/- 2.15 D of anisometropia. Most conditions causing vision impairment such as albinism were associated with low amounts of hyperopia. Moderate myopia was observed in children with ROP. CONCLUSIONS: The relative frequency of ocular conditions causing vision impairment in children has changed since the 1970s. Children with vision impairment often have an associated ametropia suggesting that the emmetropization system is also impaired.

Adolescent↗

Diabetic retinopathy in people aged 70 years or older. The Oulu Eye Study.

AIMS: To evaluate the presence and severity of diabetic retinopathy and the value of retinopathy screening in people aged 70 years or older. METHODS: In a population based study on 500 of 560 eligible (89%) people aged 70 years or older, signs of diabetic retinopathy were evaluated through dilated pupils by an ophthalmologist using photographic and/or ophthalmoscopic methods. RESULTS: 23% of the study population (113/500) had diabetes mellitus. Signs of diabetic retinopathy were found in 24 people (21% of the diabetic population). Retinopathy changes were graded as mild to moderate non-proliferative retinopathy (NPDR) in 40 eyes (18 people), severe NPDR (preproliferative) in five eyes (four people), and proliferative in three eyes (two people). Preproliferative or proliferative changes were present in four people (3.5% of the diabetic population) and diabetic maculopathy was diagnosed in nine (8% of the diabetic population). Laser treatment was considered to be indicated in seven people for maculopathy, and in two for proliferative changes. In four people the visual acuity was reduced to a low vision level as a result of diabetic retinopathy. CONCLUSION: In spite of the high prevalence of diabetes mellitus in the elderly population, the prevalence of vision threatening diabetic retinopathy, particularly proliferative retinopathy, is low. Ophthalmoscopically, reliable information on fundus changes could be obtained in 94%, but photographs were gradable in only 76% of the diabetic population. Therefore, the value of photographic screening for diabetic retinopathy in this age group is poor in comparison with younger age groups.

Aged↗

Keeping an eye on vision: new tools to preserve sight and quality of life. A roundtable discussion, Part 2.

Research is pointing the way to new therapies for the eye diseases of aging. A gene that appears related to glaucoma has been identified, and a safe and effective inhibitor for aldose reductase is being sought for patients with diabetic retinopathy. Refinements in cataract surgery continue to improve the high success rate of this procedure. Physicians can educate their patients to participate in vision protection, through control of blood sugars, compliance with glaucoma medications, and the use of the Amsler grid by those at risk for macular degeneration. When vision cannot be corrected to the normal range, low vision rehabilitation offers magnification and new high-tech devices for optimizing independent patient function.

Age Factors↗

A longitudinal study of visual acuity and visual rehabilitation needs in an urban Swedish population followed from the ages of 70 to 97 years of age.

PURPOSE: To investigate the longitudinal change in visual acuity (VA) in the oldest members of the elderly population, to estimate future numbers of people with visual impairments, and to estimate needs for and the effects of visual rehabilitation. METHODS: In the Gerontological and Geriatric Population Studies in Gothenburg, Sweden (H 70), subjects underwent repeated eye examinations at the ages of 70, 82, 88, 95 and 97 years. Logistic regression analysis was used to estimate the probability of independent living as a function of distance VA at different ages. RESULTS: Rates of normal VA (>or= 0.8) declined from 86% of the study group at age 70 to 7% of the study group at age 95 (0% at age 97). The incidence of VA <or= 0.1 increased from 1.4% at age 70 to 27% (all women) at age 97. The deterioration was faster at higher ages. No statistically significant difference in best-corrected distance VA between genders was found. A substantial improvement was achieved by correcting refractive errors. There was a statistically significant correlation between distance VA and the probability of independent living at all ages except age 97. At ages 95 and 97, about 50% of the study group were able to read newspaper print with best-corrected glasses. CONCLUSIONS: The number of old people with impaired vision will increase. People aged 80 years and older should have regular eye-screening in order to preserve vision and present conditions of living. Cataract surgery and low vision rehabilitation should be offered when the subject can still benefit from it, preferably during their 80s at the latest.

Activities of Daily Living↗

Subepithelial corneal amyloid deposits in a case of congenital glaucoma: a case report.

PURPOSE: To report a rare association of subepithelial amyloid deposits in a long-standing case of congenital glaucoma. METHODS: A 5-year-old girl was brought to the emergency service with complaints of bleeding from the left eye after injury to the eye with the door handle. Parents gave history of enlarged black portion of the eye since birth with increasing white opacity from the age of 6 months. On examination under general anesthesia, the left eye showed a limbal tear extending from 7 to 3.30 o'clock position and uveal prolapse. The right eye showed corneal edema, megalocornea, central white raised plaque, and high intraocular pressure. A diagnosis of bilateral congenital glaucoma with open globe injury, left eye, corneal scarring with degeneration, right eye was made and was advised enucleation. The enucleated eye was submitted for routine histologic examination. At a 3-year follow-up, there was an increase in the corneal scarring, with no significant improvement in vision. The child refused keratoplasty and was referred to low vision centre for visual rehabilitation. RESULTS: The enucleated eye was distorted and filled with blood. The cornea showed confluent pink homogenous wavy deposits in the subepithelial region. These deposits appeared brick red with Congo Red stain and showed apple green birefringence when viewed under polarized filters, confirming the amyloid nature of the deposits. There was loss of ganglion cell layer in the detached retina. CONCLUSION: The subepithelial amyloid deposits, presumably bilateral, in advanced case of congenital glaucoma were possibly secondary to the long-standing edema, scarring and vascularization. These secondary changes should be kept in mind as they could contribute to further deterioration in vision in advanced cases.

Amyloidosis↗

Detection of ophthalmoscopically occult maculopathy by focal electroretinography.

We performed focal electroretinography (FERG) in 10 patients with reduced vision of unknown cause. No patient gave a family history of uncorrectably reduced vision, and none had taken any drug known to damage the retina. Visual acuity claims ranged from 20/40 to finger counting. Color discrimination was reduced in all but one patient. Visual field sensitivity was reduced nonspecifically in five of the six patients who could perform perimetry reliably. Ophthalmoscopy showed no pertinent abnormality in four of 10 patients, mildly reduced foveal reflex in two of 10, arteriolar narrowing in two of 10, foveal pigment disturbance in one of 10, and preretinal gliosis in one of 10. Flash visual evoked potential (VEP) testing showed no abnormality in seven of 7 patients. The pattern VEP was reduced or delayed in five of 5 patients, only one of whom showed the expected amplitude loss with decreasing check size. Five patients completed full-field electroretinography, six patients completed fluorescein angiography, and none showed pertinent abnormality on either test. FERG was performed in both eyes of seven patients and in one eye of three others. Signals were non-recordable from four eyes, abnormal in nine, equivocal in three, and normal in one. The severity of FERG abnormality did not correlate with the severity of acuity loss. FERG abnormalities were found in fourteen of 17 eyes of 10 patients with vision loss out of proportion to clinical findings. In these patients only one of 5 pattern VEP tests, none of 5 full-field ERGs, and none of 7 fluorescein angiograms suggested correspondingly severe maculopathy. The FERG results in these cases mitigated suspicions of nonorganic vision loss and permitted speedier referral to retinal disease and low vision specialists.

Adolescent↗

Visual function: the problem with eccentricity.

Age-related macular degeneration (AMD) is the leading cause of blindness in developed countries. With an ageing population, the prevalence of such a condition has resulted in a large proportion of the population relying on peripheral vision to undertake activities of daily living. Peripheral vision is not a scaled-down version of the fovea, simply requiring larger print or increased contrast for detection of objects or reading text. Even when print size is scaled and eye movements are minimised, the peripheral retina cannot perform at the level of the foveal region. Understanding how and why reading performance is limited as a function of eccentricity has important implications for how we approach rehabilitation of patients with central visual loss. This brief review of the extensive literature on reading with peripheral vision and the research aimed at better reading rehabilitation for low vision patients focuses on why many of the problems associated with the reduced reading capability of peripheral vision cannot be completely solved with magnification, reducing eye movements or modifying print.

Blindness↗

Benefits of electronic vision enhancement systems (EVES) for the visually impaired.

PURPOSE: To examine whether objective performance of near tasks is improved with various electronic vision enhancement systems (EVES) compared with the subject's own optical magnifier. DESIGN: Experimental study, randomized, within-patient design. METHODS: This was a prospective study, conducted in a hospital ophthalmology low-vision clinic. The patient population comprised 70 sequential visually impaired subjects. The magnifying devices examined were: patient's optimum optical magnifier; magnification and field-of-view matched mouse EVES with monitor or head-mounted display (HMD) viewing; and stand EVES with monitor viewing. The tasks performed were: reading speed and acuity; time taken to track from one column of print to the next; follow a route map, and locate a specific feature; and identification of specific information from a medicine label. RESULTS: Mouse EVES with HMD viewing caused lower reading speeds than stand EVES with monitor viewing (F = 38.7, P <.001). Reading with the optical magnifier was slower than with the mouse or stand EVES with monitor viewing at smaller print sizes (P <.05). The column location task was faster with the optical magnifier than with any of the EVES (F = 10.3, P <.001). The map tracking and medicine label identification task was slower with the mouse EVES with HMD viewing than with the other magnifiers (P <.01). Previous EVES experience had no effect on task performance (P >.05), but subjects with previous optical magnifier experience were significantly slower at performing the medicine label identification task with all of the EVES (P <.05). CONCLUSIONS: Although EVES provide objective benefits to the visually impaired in reading speed and acuity, together with some specific near tasks, some can be performed just as fast using optical magnification.

Aged↗

Bardet-Biedl syndrome.

This case report describes the presentation of a patient with Bardet-Biedl syndrome. Bardet-Biedl Syndrome is an autosomal recessive condition that includes retinal dystrophy, dystrophic extremities (commonly polydactyly), obesity, hypogenitalism, and renal disease. Cognitive deficit has also been considered part of the syndrome. The historically associated Laurence-Moon syndrome includes spastic paraparesis but not the obesity and polydactyly. They are now considered separate conditions. The most common feature of Bardet-Biedl syndrome is retinal dystrophy. The appearance of the retina in the condition is quite variable with typical retinitis pigmentosa being present in only a minority of cases. The associated optic atrophy can be primary in nature and might play a role in the decreased central vision. Diagnosis of the condition is important for visual prognosis and low vision management. The renal disease often goes undetected until specific radiological testing is done after diagnosis of Bardet-Biedl syndrome. This is significant in that early death often occurs in this condition because of the renal disease.

Adult↗

[Osteoporosis--prevention, diagnosis and treatment. A systematic literature review. SBU conclusions and summary].

A report by the Swedish Council on Technology Assessment in Health Care (SBU) has reviewed, classified, and graded the scientific literature on prevention, diagnosis and treatment of osteoporosis. This article summarizes the overall conclusions. There is no scientific evidence to support the use of bone density measurement as a screening method in healthy, middle-aged individuals. Patients with osteoporosis-related fractures are an undertreated group as regards pharmacotherapy and other interventions to prevent new fractures. There are some evidence that physical exercise to reduce falls among elderly and hip protectors can prevent fractures. The combination therapy of calcium and vitamin D is shown to reduce the risk for hip fractures and other fractures except vertebral fractures in elderly women. Bisphosphonates are shown to reduce the number of fractures, mainly vertebral fractures. SERM is shown to reduce the risk for vertebral fractures in postmenopausal women with osteoporosis. Important risk factors for osteoporosis-related fractures that can be treated are physical inactivity, low weight, tobacco smoking, high alcohol consumption, tendency to fall, impaired vision, low exposure to sunlight, and use of corticosteroids. No particular diagnostic method or measurement site is optimal for determining the risk for fracture in all parts of the skeleton. The various measurement methods--dual energy x-ray absorbtiometry (DXA), ultrasound (QUS), and computed tomography (QCT)--are not directly comparable.

Aged↗

Age-related vision changes: a primary care guide.

Visual impairment becomes more prevalent with age. A person has "low vision" when legally blind or partially sighted. In addition, many older patients have functional visual impairment that affects their ability to read, even with corrective lenses. Normal visual changes that occur with aging include presbyopia, decreased contrast sensitivity, decreased dark/light adaptation, and delayed glare recovery. The four most prevalent age-related ocular diseases are macular degeneration, open-angle glaucoma, cataract, and diabetic retinopathy. The primary care practitioner can identify patients with visual problems with a careful history and in-office tests of visual acuity. Patients with visual impairments should be referred to an eye care practitioner for a more comprehensive ocular evaluation.

Age Factors↗

[Results of Iodine-125 radiotherapy in the treatment of uveal melanoma].

PURPOSE: To evaluate our experience in the treatment of uveal melanoma by means of Iodine-125 brachytherapy. A reprospective case series study. MATERIAL AND METHOD: Patients diagnosed of uveal melanoma and treated with Iodine-125 brachytherapy in the Ciudad Sanitaria y Universitaria de Bellvitge (CDUV), from September 1996 to December 2000 and follow up of more than one year. RESULTS: During the period of study, 145 patients were diagnosed of uveal melanoma, of which, 77 were treated with Iodine-125 COMS type plaques; among these, 58 were elegible for this study. After a mean of 2.4 year follow up period (878 days) a mean reduction in height of 53.84% and a mean reduction in volume of 75.88% was observed. As for visual acuity, 32.7% of patients presented a vision of 0.1 or better in last follow up check; 13.5% presented low vision at the moment of diagnosis and continued the same up to last follow up check. The rest of patients experienced loss which conditioned vision to less than 0.1. As for complications, we have observed transient diplopia (8.6%), cataract (3.4%), vitreous bleeding (10.3%), neovascular glaucoma (6.8%), radiation retinopathy (17.24%), radiation neuropathy (6.8%), posterior scleritis (2%), pigmental scattering (2%), tumor progression (2%), endophtalmitis (2). Secondary enucleations were carried out in 6.8% of patients. Metastatic disease was observed in 15.5% of the patients. CONCLUSIONS: Brachytherapy with Iodine-125 may induce significant regression in most of patients affected of uveal melanoma, with good preservation of visual acuity and a low rate of complications.

Adult↗

[Visudyne photodynamic therapy and feeder vessel occlusion: rationale of a synergistic association and clinical options].

PURPOSE: Visudyne photodynamic therapy (PDT) has provided considerable improvement in patient care of subfoveal choroidal neovascularization (CNV). Patients tend to loose vision for a few months after the initial treatment, but the 4-year proven stability in vision most often provides an acceptable quality of life, sometimes with additional low vision rehabilitation. The initial visual acuity loss, borderline cost-effectiveness, and subgroups of patients not responding to PDT warrant improving the symptomatic treatment of subfoveal CNV. Today, the most tempting solution would be to combine PDT with an occlusion of the feeder vessel (FV). METHODS: Two patients are described in whom the feeder vessel was occluded using modifications of the classic PDT treatment method. The FV was identified in both patients using fluorescein and indocyanine green angiographies at a recorded video rate using a modified scanning laser ophthalmoscope (Rodenstock SLO). The feeder vessel of the first patient was occluded by minimal photocoagulation immediately after a Visudyne PDT treatment in order to take advantage of the reduced blood flow within the feeder vessel. The second patient presenting a subfoveal FV was treated using a modified PDT treatment called feeder-vessel PDT. The photosensitizing agent was activated by a first classic spot covering the lesion, followed immediately by a small spot focused on the feeder vessel. RESULTS: Both subfoveal CNVs were successfully and selectively occluded and some visual acuity was gained following the treatment. CONCLUSION: Occlusion of the feeder vessel is an appealing clinical option that is complementary to Visudyne PDT. Both treatment methods presented here could provide additional options to close subfoveal CNV with an optimal efficacy-risk ratio.

Angiography↗

The impact of diabetic retinopathy on participation in daily living.

OBJECTIVE: To determine the restriction of participation in daily activities of people with diabetic retinopathy using the Impact of Vision Impairment questionnaire. METHODS: Individuals with diabetic retinopathy and a visual acuity (VA) worse than 20/40 or 6/12 in the better eye were eligible. Participants answered demographic questions and had VA information abstracted from medical records. If VA information was unavailable, it was assessed by an orthoptist. MAIN OUTCOME MEASURES: All participants completed the Impact of Vision Impairment questionnaire, which was either self-administered or interviewer administered. The physical and mental health components were assessed using the Medical Outcomes Study 12-Item Short Form (SF-12) questionnaire. RESULTS: Forty-five participants (mean age, 67.5 years) were recruited, with almost 70% (30/45) recording a VA worse than 20/60 or 6/18 in the better eye. The median duration of vision loss was 2.0 years. The highest restriction was reported for the Leisure and Work, Mobility, and Consumer and Social Interaction domains (mean, 3.0, 2.8, and 2.8, respectively), compared with the Emotional Reaction to Visual Loss and Household and Personal Care domains (mean, 2.3 and 2.1, respectively) (P<.005). The activities with the greatest restriction of participation were reading print, mobility, work, and leisure. A poorer VA in the better eye correlated independently with increased restriction of participation, as measured by the Impact of Vision Impairment questionnaire scores (partial correlations, 0.29-0.41; P< or =.03). CONCLUSION: Low-vision rehabilitation services aiming to improve outdoor mobility, print reading, participation in leisure activities, and psychological health may be an effective strategy to help people with diabetic retinopathy increase their participation in daily activities.

Activities of Daily Living↗

A review of current knowledge on Electronic Vision Enhancement Systems for the visually impaired.

Magnification can be provided to assist those with visual impairment to make the best use of remaining vision. Electronic transverse magnification of an object was first conceived for use in low vision in the late 1950s, but has developed slowly and is not extensively prescribed because of its relatively high cost and lack of portability. Electronic devices providing transverse magnification have been termed closed-circuit television (CCTVs) because of the direct cable link between the camera imaging system and monitor viewing system, but this description generally refers to surveillance devices and does not indicate the provision of features such as magnification and contrast enhancement. Therefore, the term Electronic Vision Enhancement Systems (EVES) is proposed to better distinguish and describe such devices. This paper reviews current knowledge on EVES for the visually impaired in terms of: classification; hardware and software (development of technology, magnification and field-of-view, contrast and image enhancement); user aspects (users and usage, reading speed and duration, and training); and potential future development of EVES.

Persons with Disabilities↗

Vision rehabilitation in the case of blindness.

This article examines the various vision rehabilitation procedures that are available for early and late blindness. Depending on the pathology involved, several vision rehabilitation procedures exist, or are in development. Visual aids are available for low vision individuals, as are sensory aids for blind persons. Most noninvasive sensory substitution prostheses as well as implanted visual prostheses in development are reviewed. Issues dealing with vision rehabilitation are also discussed, such as problems of biocompatibility, electrical safety, psychosocial aspects, and ethics. Basic studies devoted to vision rehabilitation such as simulation in mathematical models and simulation of artificial vision are also presented. Finally, the importance of accurate rehabilitation assessment is addressed, and tentative market figures are given.

Blindness↗

The impact of Vision 2020 on global blindness.

INTRODUCTION: Recent data suggest that there are 37 million blind people and 124 million with low vision, excluding those with uncorrected refractive errors. The main causes of global blindness are cataract, glaucoma, corneal scarring (from a variety of causes), age-related macular degeneration, and diabetic retinopathy. CONCLUSION: It would appear that the global Vision 2020 initiative is having an impact to reduce avoidable blindness particularly from ocular infections, but more needs to be done to address cataract, glaucoma, and diabetic retinopathy.

Blindness↗