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Query: UMLS:C0344232 (blurred vision)
 2,072 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In a criminal case I produced photographs in court to demonstrate how blurred vision is for myopic with a refractive error of 10 diopters who does not wear glasses. It was attempted to take the different variable circumstances into consideration, especially the width of the pupil. As there are no known comparable pictures, they may be useful in teaching.
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PMID:[How blurred is vision in myopia? -- An attempt at demonstration by means of photography (author's transl)]. 742 Oct 13

A 33-year-old woman had progressive blurred vision 2 weeks after uneventful laser in situ keratomileusis surgery. Initial satisfactory uncorrected visual acuity (UCVA) was complicated by postoperative dry eye and drug toxicity. Slitlamp biomicroscopy revealed diffuse punctate epithelial keratitis and inferior corneal epithelial defect with rolled-up epithelium on the flaps and the inferior unoperated cornea in both eyes. Diffuse inflammatory cell infiltrates were evident in the stroma. Stromal thinning was evident on serial Orbscan (Bausch & Lomb) and pachymetry examinations, and a hyperopic shift of almost +6 diopters was observed in the refractive error in both eyes. These examinations showed a gradual recovery of stromal thickness after copious hydration with balanced salt solution. The UCVA was 1.0 in both eyes after corneal rehydration.
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PMID:Toxic keratopathy-related corneal dehydration after laser in situ keratomileusis. 1612 7

The refractive errors, myopia and hyperopia, are optical defects of the visual system that can cause blurred vision. Uncorrected refractive errors are the most common causes of visual impairment worldwide. It is estimated that 2.5 billion people will be affected by myopia alone within the next decade. Experimental, epidemiological and clinical research has shown that refractive development is influenced by both environmental and genetic factors. Animal models have showed that eye growth and refractive maturation during infancy are tightly regulated by visually guided mechanisms. Observational data in human populations provide compelling evidence that environmental influences and individual behavioral factors play crucial roles in myopia susceptibility. Nevertheless, the majority of the variance of refractive error within populations is thought to be because of hereditary factors. Genetic linkage studies have mapped two dozen loci, while association studies have implicated more than 25 different genes in refractive variation. Many of these genes are involved in common biological pathways known to mediate extracellular matrix (ECM) composition and regulate connective tissue remodeling. Other associated genomic regions suggest novel mechanisms in the etiology of human myopia, such as mitochondrial-mediated cell death or photoreceptor-mediated visual signal transmission. Taken together, observational and experimental studies have revealed the complex nature of human refractive variation, which likely involves variants in several genes and functional pathways. Multiway interactions between genes and/or environmental factors may also be important in determining individual risks of myopia, and may help explain the complex pattern of refractive error in human populations.
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PMID:Nature and nurture: the complex genetics of myopia and refractive error. 2115 61

The hypothesis that visual perception and mental imagery are equivalent has never been explored in individuals with vision defects not preventing the visual perception of the world, such as refractive errors. Refractive error (i.e., myopia, hyperopia or astigmatism) is a condition where the refracting system of the eye fails to focus objects sharply on the retina. As a consequence refractive errors cause blurred vision. We subdivided 84 individuals according to their spherical equivalent refraction into Emmetropes (control individuals without refractive errors) and Ametropes (individuals with refractive errors). Participants performed a vividness task and completed a questionnaire that explored their cognitive style of thinking before their vision was checked by an ophthalmologist. Although results showed that Ametropes had less vivid mental images than Emmetropes this did not affect the development of their cognitive style of thinking; in fact, Ametropes were able to use both verbal and visual strategies to acquire and retrieve information. Present data are consistent with the hypothesis of equivalence between imagery and perception.
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PMID:Refractive errors affect the vividness of visual mental images. 2375 86

Purpose. To report a case of bilateral punctate inner choroidopathy (PIC). Case Report. A 26-year-old Caucasian woman presented with bilateral blurred vision with one year of evolution. There was no relevant systemic disease or family history. Best-corrected visual acuity in the right eye was 20/30 and in the left eye was 20/20; there was no clinically significant refractive error. Fundoscopy evidenced multiple, small, round, yellow-white lesions limited to the posterior pole of both eyes, with greater macular involvement in the RE. There were no signs of inflammation in the anterior chamber or vitreous cavity. Fluorescein angiography revealed the presence of multiple hyperfluorescent lesions more evident in the later stages of the angiogram in both eyes. On indocyanine green angiography, these lesions appeared hypofluorescent in both early and late phases. Optical coherence tomography showed the presence of focal elevations of the retinal pigment epithelium with underlying hyporeflective space, bilaterally. Laboratory and imaging evaluation for evidence of autoimmune and infectious diseases were negative. Conclusion. The PIC is a relatively uncommon condition. In this report, an attempt has been made to describe a classic clinic presentation of this disease in a young and female patient.
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PMID:Punctate Inner Choroidopathy. 2606 May 91

Multifocal intraocular lenses are increasingly used in the management of pseudophakic presbyopia. After multifocal intraocular lens implantation, most patients do not need spectacles or contact lenses and are pleased with the result. Complications, however, may affect the patient's quality of life and level of satisfaction. Common problems with multifocal lenses are blurred vision and photic phenomena associated with residual ametropia, posterior capsule opacification, large pupil size, wavefront anomalies, dry eye, and lens decentration. The main reasons for these are failure to neuroadapt, lens dislocation, residual refractive error, and lens opacification. To avoid patient dissatisfaction after multifocal intraocular lens implantation, it is important to consider preoperatively the patient's lifestyle; perform an exhaustive examination including biometry, topography, and pupil reactivity; and explain the visual expectations and possible postoperative complications.
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PMID:Multifocal intraocular lenses: An overview. 2836 83

Refractive errors are the product of a mismatch between the axial length of the eye and its optical power, creating blurred vision. Uncorrected refractive errors are the second leading cause of worldwide blindness. One refractive error currently attracting significant scientific interest is myopia, mostly owing to the recent rise in its prevalence worldwide and associated ocular disease burden. This increase in myopia prevalence has also been rapid, suggesting environmental influences in addition to any genetic influences on eye growth. This review defines refractive errors, describes their prevalence, and presents evidence for the influence of genetic and environmental factors related to refractive error development.
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PMID:Origins of Refractive Errors: Environmental and Genetic Factors. 3152 41