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Childhood cataract is cataract that occurs at birth or in childhood. [1] It may be congenital or acquired. Congenital cataracts are defined as the presence of lens opacification during childhood. [2] About 1.14 million children in the world are blind. [3] Cataracts are the leading cause of blindness in children. [4]
This test can be used for routine ocular screening by nurses, pediatricians, family practitioners, and optometrists. Retinoscopy through the child's undilated pupil is helpful for assessing the potential visual significance of an axial lens opacity in a pre-verbal child. Any central opacity or surrounding cortical distortion greater than 3 mm ...
The analyser will provide a lens strength and type (either spherical and/or cylindrical), if required for the test. In these instances, wire-rimmed trial lenses are generally used, with the cylindrical lens placed closest to the patient so the axis is easily read. The clinician can alter the fixation targets as per necessary (see Fixation ...
When refractive errors in children are not treated, the child may be at risk of developing ambylopia, where vision may remain permanently blurry. [33] Because young children typically do not complain of blurry vision, the American Academy of Pediatrics recommends that children have yearly vision screening starting at three years old so that unknown refractive errors or other ophthalmic ...
This test detects the afferent pupil defect, also referred to as the Marcus Gunn pupil. It is conducted in a semidarkened room. In a normal reaction to the swinging-flashlight test, both pupils constrict when one is exposed to light. As the light is being moved from one eye to another, both eyes begin to dilate, but constrict again when light ...
An immature cataract has some transparent protein, but with a mature cataract, all the lens protein is opaque. In a hypermature or Morgagnian cataract, the lens proteins have become liquid. Congenital cataract, which may be detected in adulthood, has a different classification and includes lamellar, polar, and sutural cataracts. [50] [51]
A lens is made of two curved surfaces, and an aspheric lens is a lens where one or both of those surfaces is not spherical. Further research and development is being conducted [ citation needed ] to determine whether the mathematical and theoretical benefits of aspheric lenses can be implemented in practice in a way that results in better ...
A cataract is an opacity that develops in the crystalline lens of the eye. [9] The word cataract literally means, "curtain of water" or "waterfall" as rapidly running water turns white, so the term may have been used metaphorically to describe the similar appearance between mature ocular opacities and water fall.