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Canine and human visual cortex intact and responsive despite early retinal blindness from RPE65 mutation.

BACKGROUND: RPE65 is an essential molecule in the retinoid-visual cycle, and RPE65 gene mutations cause the congenital human blindness known as Leber congenital amaurosis (LCA). Somatic gene therapy delivered to the retina of blind dogs with an RPE65 mutation dramatically restores retinal physiology and has sparked international interest in human treatment trials for this incurable disease. An unanswered question is how the visual cortex responds after prolonged sensory deprivation from retinal dysfunction. We therefore studied the cortex of RPE65-mutant dogs before and after retinal gene ther…

Fear of blindness in the Collaborative Initial Glaucoma Treatment Study: patterns and correlates over time.

PURPOSE: The objective of this study was to describe the prevalence of fear of blindness (FOB) and the factors associated with FOB during 5 years of follow-up in the Collaborative Initial Glaucoma Treatment Study. DESIGN: Randomized controlled clinical trial. PARTICIPANTS: A total of 607 newly diagnosed patients with open-angle glaucoma were recruited from 14 clinical centers in the United States. METHODS: Patients were assigned randomly either to initial medical therapy or initial trabeculectomy. Study participants received clinical examinations and quality-of-life (QOL) evaluations at bas…

A proposed rapid methodology to assess the prevalence and causes of blindness and visual impairment.

PURPOSE: To determine whether a sample of the 50-year-old and above population would provide comparable information to a total population-based survey. METHODS: In 1996, a national eye survey of the total population in The Gambia was undertaken and the results concerning the prevalence and distribution of blindness and low vision have been reported. The same data set was used to analyse the prevalence and causes of blindness and low vision in people aged 50 years and above, and to compare the findings with the total population. RESULTS: Of 55 bilaterally blind people in the total population,…

Blindness and low vision in adults in Ozoro, a rural community in Delta State, Nigeria.

BACKGROUND: The objective of this article is to determine the prevalence and causes of blindness and low vision in Ozoro, a rural town of Delta State in Nigeria, in order to provide baseline information for planning a prevention of blindness programme. METHODS: A cross sectional study using a stratified random sampling method was used to select the compounds. The five communities in the town formed the different sub-groups or strata. Visual acuity were recorded for all adults 40 years and older. Persons who had visual acuity less than 6/18 were further examined to determine the cause of low v…

Causes of severe visual impairment and blindness in schools for visually handicapped children in Iran.

AIMS: This survey was conducted on children in schools for the blind in Tehran (from 2002 to 2003) to determine the causes of severe visual impairment and blindness and to identify preventable and treatable conditions. METHODS: The study was performed on 362 students at different grades in three schools for the blind. Patient sex, age, family history of blindness or low vision, visual acuity, causes of blindness, and treatable and preventable conditions were studied. RESULTS: Of the 362 cases, 210 (58%) were boys and 152 (42%) were girls. Mean age was 13.5 (SD 4) years. Severe visual loss wa…

Prevalence and causes of blindness and low vision in leprosy villages of north eastern Nigeria.

AIMS: To determine the prevalence and spectrum of ocular pathology, and the prevalence and causes of blindness and low vision in leprosy villages of north eastern Nigeria. METHODS: People affected by leprosy, aged 30 years and above, resident in eight leprosy villages were invited to participate. Ocular examination was undertaken of each consenting individual. RESULTS: 480 people were examined. 456 (48%) of 960 eyes had at least one ocular lesion, but only 37% of all lesions were leprosy related and potentially sight threatening. The prevalence of blindness (VA<3/60 with available correction…

ERGs in female carriers of incomplete congenital stationary night blindness (I-CSNB). A family report.

ERG findings in five sisters are reported. By pedigree analysis, four of the five must be obligate carriers for I-CSNB since their sons were affected (impaired night vision, reduced visual acuity, variable ametropia, congenital nystagmus and ERG with both scotopic and photopic b-wave reduced amplitude). The fifth was childless at the time of examination and her ERG analysis was normal. Three of the four obligate carriers showed significant reduction in the sum of the OPs amplitude as previously reported as being an electrophysiological signs in female carriers: two without alteration in other

Onchocerca volvulus keratitis (river blindness) is exacerbated in BALB/c IL-4 gene knockout mice.

To determine the outcome of Onchocerca volvulus keratitis in IL-4(-/-) BALB/c mice, animals were immunized subcutaneously and injected into the corneal stroma with soluble O. volvulus antigens. IL-4(-/-) BALB/c mice had a deviated cellular response, with decreased serum IgE and IgG1 and elevated IgG2a compared with control BALB/c mice. In marked contrast to control BALB/c, C57BL/6, and IL-4(-/-) C57BL/6 mice, IL-4(-/-) BALB/c mice developed severe corneal opacification and neovascularization that was associated with a pronounced neutrophil infiltrate to the corneal stroma. STAT-6(-/-) BALB/c m

Central retinal artery occlusion by proxy: a cause for sudden blindness in an airline passenger.

The use of gas media in ophthalmologic procedures is relatively commonplace. Scleral buckle and pneumatic retinopexy procedures using air-gas mediums are a widely accepted treatment for retinal detachment. We present a patient who had a scleral buckle with pneumatic retinopexy performed and subsequently flew in a commercial airliner 2 wk later. The patient experienced sudden blindness due to central retinal artery occlusion brought about by expansion of the air bubble when the aircraft reached cruise altitude and a cabin pressure of 8000 ft. The intraocular pressure exceeded the central artery…

A case of subarachnoid hemorrhage presenting with temporary blindness disclosed by Xe CT-CBF study.

A 69-year-old male with right oculomotor palsy caused by non-ruptured right internal carotid-posterior communicating artery aneurysm suddenl … acuity were almost cured. We conclude that Xe-CT CBF study supports the hypothesis of the temporary blindness due to the optic chiasm and nerves injuries by subarachnoid hemorrhage.

Visual loss and central venous catheterization: cortical blindness and hemianopsia after inadvertent subclavian artery entry.

A case of presumed embolic transient ischemic episodes and multifocal infarcts to the occipital and parietal cortices and the cerebellum of a young woman with ulcerative colitis is reported. These episodes were manifested by multifocal neurologic deficits including cortical blindness, visual hallucinations, and homonymous hemianopsia. They correlated with parenteral nutrition via a central line, presumed venous, but found to be in the subclavian artery. The complications of central venous lines are reviewed. The need for attention to neighborhood structures and unexpected symptoms, in view of …

[Transient cortical blindness and convulsion mimicking a hemorrhagic complication during embolization of the cerebellar AVM].

We report a case of transient cortical blindness and convulsions during embolization of the cerebellar AVM. A 29-year-old man was admitted to our hospital with subarachnoid hemorrhage. Cerebral angiography showed the right cerebellar AVM fed by the right superior cerebellar artery. Preoperative embolization of the AVM was performed. During embolization, the patient lost consciousness suddenly and appeared to be in a decerebrate posture. About 15 minutes later, the patient came around and complained of total blindness. Cerebral angiography revealed the disappearance of the aneurysm and AVM. The…

Association of high-dose intravenous methylprednisolone with reversal of blindness from lightning in two patients.

OBJECTIVE: To report possibly beneficial effects of treatment with high-dose corticosteroids given intravenously to two patients with loss of vision after lightning strikes. DESIGN: Case reports. PARTICIPANTS: Two patients who suffered the effects of a lightning strike. INTERVENTION: High-dose intravenous methylprednisolone (NASCIS-2 Protocol). MAIN OUTCOME MEASURES: Vision recovery, pupil responses, and optic nerve appearance. RESULTS: One patient had unilateral ophthalmoscopically visible abnormality with light perception vision and a relative afferent defect in that eye; vision recover

Chlamydia trachomatis: the role of cellular and humoral immune mechanisms in the development of blindness.

Ocular infection with Chlamydia trachomatis leading to trachoma is the commonest cause of treatable blindness worldwide. Although effectively controlled by improved sanitation, a chlamydial vaccine may prove a more cost-effective method of protection against this disease in the medium term. The development of vaccines against Chlamydia trachomatis has been hampered by a lack of understanding of the immune responses leading to protection or pathology, particularly in humans. Although a strong cell-mediated immune response (T helper lymphocyte type 1) is almost certainly necessary to resolve int…

[Contrast sensitivity of several blindness-inducing eye diseases and the influence of tinted filter lens].

OBJECTIVES: To evaluate the effects of tinted filter lens on the visual rehabilitation of blind and low vision patients induced by optic nerve atrophy, glaucoma and retinitis pigmentosa. METHODS: The contrast sensitivity of 22 cases with optic nerve atrophy (34 eyes), 17 glaucoma (30 eyes), 18 retinitis pigmentosa (30 eyes) and 30 normal people (60 eyes) with and without yellow and red filter lens was tested. RESULTS: The results demonstrated that a yellow filter lens could improve the optic nerve atrophy patient's contrast sensitivity at 1.5, 3, 6 and 12 c/deg, while a red filter lens could

Pathogenesis of acute monocular blindness from leaking anterior communicating artery aneurysms: report of six cases.

This report describes six cases of leaking anterior communicating aneurysms, collected over 37 years, that caused acute monocular blindness. In two cases, surgical and pathologic evidence demonstrated the pathogenic mechanism: As the aneurysm enlarges, the down-pointing dome compresses the optic nerve from above and adheres to it. When the aneurysm ruptures through the adherent dome, it bleeds directly into the optic nerve, resulting in severe headache and monocular blindness. The other cases also suggest an alternative mechanism, namely, direct optic nerve compression by the aneurysm.

Prevention of blindness in leprosy: an overview of the relevant clinical and programme-planning issues.

Visual disability continues to be a significant problem in leprosy patients due to cataract, chronic iridocyclitis, and corneal disease. Clinical and epidemiological aspects of these problems are described and the current status of eye care in leprosy programmes is discussed.

- слепота и нарушение зрения в регионе, эндемичном для онхоцеркоза в Центральноафриканской Республике.

АИСЮ: В округе Боссангоа, Центральноафриканская Республика, было проведено обследование слепоты и нарушения зрения на основе опроса населения. МЕТОДЫ: В общей сложности было произвольно отобрано 48 общин и обследовано 6086 человек. Результаты: Доля слепоты (видеоприемлемость у лучшего глаза менее 3/60) составила 2,2%, а у лучшего глаза - 3,0% (6/24-3/60). Основными причинами слепоты являются онхоцеркоз (73,1%), катаракта (16,4%), трахома (4,5%) и глаукома (2,2%). ЗАКЛЮЧЕНИЕ: Около 95,5% всей слепоты можно было бы предотвратить или лечить. Ожидается, что массовое распределение Иверметина предот

Совпадение в аннотации оригинала
AIMS: A population based survey of blindness and visual impairment was conducted in the district of Bossangoa, Central African Republic. METHODS: A total of 48 communities were randomly selected, and 6086 people examined. RESULTS: The prevalence of blindness (visual acuity in the better eye less than 3/60) was 2.2%, and visual impairment 3.0% (6/24 to 3/60…

On- and off-responses in the photopic electroretinogram in complete-type congenital stationary night blindness.

We examined the on- and off-responses of the photopic electroretinogram in patients with complete congenital stationary night blindness. Standard flash electroretinograms as well as those produced in a ganzfeld modified for long-duration light stimuli (500 msec) permitted the separation of on- and off-responses in four patients and four normal subjects. The amplitude and latency of the elctroretinogram on-response (a- and b-waves) and off-response (d-wave) in addition to the oscillatory potentials of the off-response in normal subjects and patients were compared. The abnormal on-response was d…