lens opacity


Also found in: Dictionary, Thesaurus, Encyclopedia.
Related to lens opacity: stye

lens opacity

Cataract, see there.

lens

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.

apochromatic lens
one corrected for both chromatic and spherical aberration.
biconcave lens
one concave on both faces.
biconvex lens
one convex on both faces.
lens cells
the only nucleated cells in the lens of the adult are those of the epithelium beneath the capsule on the rostral surface.
concave lens
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.
contact l's
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.
converging lens
one curved like the exterior of a hollow sphere; it brings light to a focus. Called also convex lens.
convex lens
see converging lens (above).
convexoconcave lens
one that has one convex and one concave face.
crystalline lens
see lens (2) (above).
dispersing lens
concave lens.
ectopic lens
see ectopia lentis.
lens fibers
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.
lens-induced uveitis
see phacolytic uveitis, phacoclastic uveitis.
lens induction
see inductive interactions.
intraocular lens
plastic lenses placed within the lens capsule after cataract surgery.
intumescent lens
see intumescent cataract.
lens luxation
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.
Enlarge picture
Lens luxation in a horse's eye. By permission from Knottenbelt DC, Pascoe RR, Diseases and Disorders of the Horse, Saunders, 2003
lens opacity
cataract.
lens sclerosis
see nuclear sclerosis.
lens subluxation
partial separation of zonular attachments, allowing some alteration in position but not movement into another chamber.
lens sutures
structures formed by the contact between caudal and rostral lens fibers resulting in Y-shaped lens stars.
References in periodicals archive ?
Nuclear lens opacity has been the most widely studied of the three lens areas.
This trial will characterize the occurrence of lens opacity ocular events, as sometimes seen in patients who are treated with high doses of inhaled corticosteroids, including a small number of patients during one phase III Alvesco trial.
Which type of lens opacity is this patient MOST likely to develop?