Ads
related to: causes of visual impairment
Search results
Results From The WOW.Com Content Network
Visual or vision impairment (VI or VIP) is the partial or total inability of visual perception.In the absence of treatment such as corrective eyewear, assistive devices, and medical treatment, visual impairment may cause the individual difficulties with normal daily tasks, including reading and walking. [6]
Leading causes include retinopathy of prematurity, vitamin A deficiency, infectious diseases (measles, newborn conjunctivitis), retinoblastoma, and congenital conditions (cataracts and glaucoma). [13] Leber congenital amaurosis primarily affects the retina, and typically severe visual impairment begins in infancy. Mutations in Aryl hydrocarbon ...
However, recent studies have shown that most cases of visually impaired children are a result of causes such as cerebral visual impairment and optic nerve anomalies. [29] This is due to a decrease in preventable or avoidable causes of blindness with the improvement and focus on maternal and neonatal healthcare worldwide. [6]
A vision disorder is an impairment of the sense of vision. Vision disorder is not the same as an eye disease. Although many vision disorders do have their immediate cause in the eye, there are many other causes that may occur at other locations in the optic pathway.
NVI and its three subtypes—cortical blindness, cortical visual impairment, and delayed visual maturation—must be distinguished from ocular visual impairment in terms of their different causes and structural foci, the brain and the eye respectively. One diagnostic marker of this distinction is that the pupils of individuals with cortical ...
Cortical visual impairment (CVI) is a form of visual impairment that is caused by a Brain problem rather than an Eye problem. (The latter is sometimes termed "ocular visual impairment" when discussed in contrast to cortical visual impairment.) Some people have both CVI and a form of ocular visual impairment.
The visual pathway consists of structures that carry visual information from the retina to the brain.Lesions in that pathway cause a variety of visual field defects. In the visual system of human eye, the visual information processed by retinal photoreceptor cells travel in the following way:
This form of myopia gets progressively worse over time. Degenerative myopia has been reported as one of the main causes of visual impairment. [72] Pseudomyopia is the blurring of distance vision brought about by spasm of the accommodation system. [73]