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A pinhole occluder is an opaque disk with one or more small holes through it, used by ophthalmologists, orthoptists and optometrists to test visual acuity. The occluder is a simple way to focus light, as in a pinhole camera, temporarily removing the effects of refractive errors such as myopia.
Pinhole glasses, also known as stenopeic glasses, are eyeglasses with a series of pinhole-sized perforations filling an opaque sheet of plastic in place of each lens.
Binocular diplopia is double vision arising as a result of strabismus (in layman's terms "cross-eyed"), the misalignment of the two eyes relative to each other, either esotropia (inward) or exotropia (outward).
Prism spectacles incorporate higher power prisms, with variable shapes and designs. The Gottlieb button prism, and the Peli superior and inferior horizontal bands are some proprietary examples of prism glasses.
A lens which includes some amount of prism correction will displace the viewed image horizontally, vertically, or a combination of both directions. The most common application for this is the treatment of strabismus. By moving the image in front of the deviated eye, double vision can be avoided and comfortable binocular vision can be achieved ...
Amsler grid, as seen by a person with normal vision. Purpose. Used to detect vision problems resulting from damage to the macula or the optic nerve [1] Test of. Central visual field. The Amsler grid, used since 1945, is a grid of horizontal and vertical lines used to monitor a person's central visual field.
A macular hole is a small break in the macula, located in the center of the eye's light-sensitive tissue called the retina. Symptoms [ edit ] If the vitreous is firmly attached to the retina when it pulls away, it can tear the retina and create a macular hole.
Low order aberrations (hyperopia, Myopia and regular astigmatism), are correctable by eyeglasses, soft contact lenses and refractive surgery. Neither spectacles nor soft contact lenses nor routine keratorefractive surgery adequately corrects high order aberrations.
Prism spectacles with a single prism perform a relative displacement of the two eyes, thereby correcting eso-, exo, hyper- or hypotropia. In contrast, spectacles with prisms of equal power for both eyes, called yoked prisms (also: conjugate prisms , ambient lenses or performance glasses ) shift the visual field of both eyes to the same extent.
Macular sparing is visual field loss that preserves vision in the center of the visual field, otherwise known as the macula. It appears in people with damage to one hemisphere of their visual cortex, and occurs simultaneously with bilateral homonymous hemianopia or homonymous quadrantanopia.