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  2. Scintillating scotoma - Wikipedia

    en.wikipedia.org/wiki/Scintillating_scotoma

    Causes. Scintillating scotomas are most commonly caused by cortical spreading depression, a pattern of changes in the behavior of nerves in the brain during a migraine. Migraines, in turn, may be caused by genetic influences and hormones.

  3. Prism correction - Wikipedia

    en.wikipedia.org/wiki/Prism_correction

    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. Other applications include yoked prism where the image is shifted an equal amount in each eye.

  4. Aberrations of the eye - Wikipedia

    en.wikipedia.org/wiki/Aberrations_of_the_eye

    Other lower-order aberrations are non- visually significant aberrations known as first order aberrations, such as prisms and zero-order aberrations (piston). Low order aberrations account for approximately 90% of the overall wave aberration in the eye.

  5. Micropsia - Wikipedia

    en.wikipedia.org/wiki/Micropsia

    Micropsia can be caused by optical factors (such as wearing glasses), by distortion of images in the eye (such as optically, via swelling of the cornea or from changes in the shape of the retina such as from retinal edema, macular degeneration, or central serous retinopathy), by changes in the brain (such as from traumatic brain injury ...

  6. Prism (optics) - Wikipedia

    en.wikipedia.org/wiki/Prism_(optics)

    An optical prism is a transparent optical element with flat, polished surfaces that are designed to refract light. At least one surface must be angled — elements with two parallel surfaces are not prisms. The most familiar type of optical prism is the triangular prism, which has a triangular base and rectangular sides.

  7. Convergence insufficiency - Wikipedia

    en.wikipedia.org/wiki/Convergence_insufficiency

    Some cases of convergence insufficiency are successfully managed by prescription of eyeglasses, sometimes with therapeutic prisms. Pencil push-ups therapy is performed at home. The patient brings a pencil slowly to within 2–3 cm (0.79–1.18 in) of the eye just above the nose about fifteen minutes per day five times per week.

  8. Eyeglass prescription - Wikipedia

    en.wikipedia.org/wiki/Eyeglass_prescription

    Prism and Base Prism refers to a displacement of the image through the lens, often used to treat strabismus and other binocular vision disorders. The prism value is measured in prism diopters , and Base refers to the direction of displacement.

  9. Prism cover test - Wikipedia

    en.wikipedia.org/wiki/Prism_Cover_Test

    The prism cover test (PCT) is an objective measurement and the gold standard in measuring strabismus, i.e. ocular misalignment, or a deviation of the eye. It is used by ophthalmologists and orthoptists in order to measure the vertical and horizontal deviation and includes both manifest and latent components. [1]

  10. Exotropia - Wikipedia

    en.wikipedia.org/wiki/Exotropia

    When one eye turns inward, outward, upward, or downward, two different pictures are sent to the brain. Thus, the brain can no longer fuse the two images coming from the two eyes. This causes loss of depth perception and binocular vision. The term is from Greek exo meaning "outward" and trope meaning "a turning".

  11. Hypertropia - Wikipedia

    en.wikipedia.org/wiki/Hypertropia

    Hypertropia is a condition of misalignment of the eyes ( strabismus ), whereby the visual axis of one eye is higher than the fellow fixating eye. Hypotropia is the similar condition, focus being on the eye with the visual axis lower than the fellow fixating eye.