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Related to lens opacity: stye
lens opacityCataract, see there.
1. a piece of glass or other transparent material so shaped as to converge or scatter light rays.
2. crystalline lens; the transparent, biconvex body separating the posterior chamber and the vitreous body of the eye. The crystalline lens refracts (bends) light rays so that they are focused on the retina. In order for the eye to see objects close at hand, light rays from the objects must be bent more sharply to bring them to focus on the retina. See also lenticular.
one corrected for both chromatic and spherical aberration.
one concave on both faces.
one convex on both faces.
the only nucleated cells in the lens of the adult are those of the epithelium beneath the capsule on the rostral surface.
one with one or both (biconvex) faces curved like a section of the interior of a hollow sphere; it disperses light rays. Called also dispersing lens.
lenses that fit directly over the cornea of the eye; used in humans for correction of refractive errors but only rarely applied in animals and then for therapeutic purposes. They can be applied in cases of severe bullous keratopathy or, after saturation with antibiotic solution, the delivery of antibiotics in high concentration to the cornea.
one curved like the exterior of a hollow sphere; it brings light to a focus. Called also convex lens.
see converging lens (above).
one that has one convex and one concave face.
see lens (2) (above).
see ectopia lentis.
elongated, modified cells oriented meridianly in concentric layers; the most peripheral contain nuclei; they interlock with each other via the medium of ball and socket interdigitations and flaps and imprints.
see inductive interactions.
plastic lenses placed within the lens capsule after cataract surgery.
see intumescent cataract.
separation of the lens from its zonular attachments, allowing displacement and freedom to move in the posterior chamber, anterior chamber or occasionally the vitreous. Occurs most commonly in dogs and is a result of trauma or as a familial trait, particularly in wirehaired Fox terriers and Sealyham terriers, predisposing to glaucoma. Luxation can occur secondary to space-occupying intraocular tumors, enlargement of the globe in chronic glaucoma, or swelling of the lens as seen in intumescent cataract.
see nuclear sclerosis.
partial separation of zonular attachments, allowing some alteration in position but not movement into another chamber.
structures formed by the contact between caudal and rostral lens fibers resulting in Y-shaped lens stars.