Ординатура / Офтальмология / Английские материалы / Slatter's Fundemental of Vetrinary Ophthalmology 4th edition_Maggs, Miller, Ofri_2008

vascular membrane extending from the ciliary body over the posterior lens capsule as a result of uveitis.

cyclitis inflammation of the ciliary body; usually seen with iritis and therefore termed iridocyclitis (or anterior uveitis). cyclo- of or pertaining to the ciliary body. cyclocryotherapy cryodestruction of the ciliary body epithelium by application of a cryoprobe to the overlying sclera to reduce the rate of aqueous humor formation and lower intraocular pressure for the treatment of glaucoma (cf.

cyclophotoablation).

cyclodialysis surgical procedure for glaucoma to establish a communication between the anterior chamber and the suprachoroidal space.

cyclodiathermy procedure for glaucoma to destroy a portion of the ciliary body by diathermy and reduce the quantity of aqueous humor produced.

cyclophotoablation destruction of the ciliary body epithelium by application of a laser probe to the overlying sclera to reduce the rate of aqueous humor formation and lower intraocular pressure for the treatment of glaucoma (cf. cyclocryotherapy).

cycloplegia paralysis of the ciliary muscle induced to reduce pain due to ciliary spasm associated with anterior uveitis.

dacryoadenitis inflammation of the lacrimal glands (orbital or third eyelid). dacryocystitis inflammation of the

lacrimal sac. dacryocystorhinography use of contrast

material for radiographic studies of the nasolacrimal drainage system.

d a c r yo c y s t o r h i n o s t o m y s u rg i c a l procedure to construct an alternate nasolacrimal drainage system into the nasal sinuses.

dark adaptation biochemical and neurologic process by which the eye becomes more sensitive to light during a period in darkness.

dazzle reflex subcortical reflex in which a rapid eye blink is elicited by a bright light shone into an eye.

decussation crossing of nerve fibers or tracts from one side of the nervous system to the opposite side, for example as occurs at the optic chiasm.

denervation hypersensitivity increased sensitivity to neural effector substance that follows postganglionic interruption of the nerve supply of organs innervated by the autonomic nervous system.

dermoid a congenital tumor consisting of skin and its appendages.

descemetocele deep corneal ulcer characterized by sufficient stromal loss that there is exposure of Descemet’s membrane.

Descemet’s membrane the basement membrane of the corneal endothelium. diopter unit of measurement of the refractive power of lenses, equal to the reciprocal of the focal length of the

lens expressed in meters.

diplopia the perception of one object as two images (“double vision”).

distichiasis condition in which a single cilium emerges from one or more meibomian (tarsal) gland orifices (cf. districhiasis, ectopic cilia, and trichiasis).

districhiasis condition in which multiple cilia emerge from one meibomian (tarsal) gland orifice (cf. distichiasis, ectopic cilia, and trichiasis).

drainage angle traditional outflow pathway by which aqueous humor exits the eye. It is bounded anteriorly by the peripheral cornea, posteriorly by the iris and ciliary muscles, internally by the pectinate ligaments, and externally by the sclera. The trabecular meshwork and ciliary cleft are contained within the iridocorneal angle. In some cases this term is used to refer to the geometric angle between the anterior surface of the iris and cornea (synonyms: filtration angle, iridocorneal angle).

dyscoria abnormally shaped pupil (adj. dyscoric).

dystrophy noninflammatory, developmental, nutritional, or metabolic abnormality.

ectasia dilation or expansion; may be toward the observer (e.g., corneal ectasia) or away from the observer (e.g., posterior scleral ectasia).

ectopia displacement or malposition, especially congenital (adj. ectopic). ectopic cilia hair/cilia protruding through

palpebral conjunctiva. The cilia usually abrade the cornea, causing pain and ulceration.

ectropion an eversion or rolling out of the eyelid.

ectropion uvea eversion of the posterior iris epithelium around the pupillary margin and into the anterior chamber; usually associated with anterior uveitis (cf. entropion uvea).

electroretinogram (ERG) a graphic record of the action potential that follows stimulation of the retina by light.

emmetropia condition in which no refractive error is present within the eye such that a distant point of light

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is properly focused onto the retina when the eye is “at rest” (i.e., not accommodating).

endophthalmitis inflammation of the intraocular contents, excluding the corneoscleral tunic (cf. panophthalmitis). enophthalmos abnormal recession of the eye within the orbit (cf.

exophthalmos).

entropion an introversion or rolling in of the eyelid.

entropion uvea posterior rolling (or inversion) of the pupillary margin into the posterior chamber; usually associated with anterior uveitis (cf. ectropion uvea).

enucleation surgical removal of the eye (cf. evisceration, exenteration).

epilation removal of hair, especially cilia.

epiphora overflow of tears due to impaired drainage, excessive production, or both.

episcleritis inflammation of the connective tissue immediately exterior to the sclera.

equine recurrent uveitis (ERU) recurrent inflammation of the anterior and/or posterior uvea in horses; the cause is unknown (older terms include “periodic ophthalmia” and “moon blindness”).

esotropia form of strabismus in which there is convergent deviation of one eye toward the midline while the other fixates normally (cf. exotropia).

euryblepharon horizontally enlarged palpebral fissure due to excessive eyelid length (also known as macropalpebral fissure).

evisceration surgical removal of the intraocular contents, with retention of the corneoscleral tunic and placement of a prosthesis within the corneoscleral shell.

exenteration (orbital) surgical removal of all the orbital tissues, including the eye and its nervous, vascular, and muscular connections.

exophthalmos abnormal protrusion of the eye from the orbit (cf. enophthalmos). May be pulsatile when associated with an orbital arteriovenous fistula.

exotropia form of strabismus in which there is divergent or lateral deviation of one eye while the other fixates normally (cf. esotropia).

fascia bulbi connective tissue sheath encircling the globe posterior to the limbus (also known as Tenon’s capsule).

filtration angle traditional outflow pathway by which aqueous humor exits the

eye. It is bounded anteriorly by the peripheral cornea, posteriorly by the iris and ciliary muscles, internally by the pectinate ligaments, and externally by the sclera. The trabecular meshwork and ciliary cleft are contained within the iridocorneal angle. In some cases this term is used to refer to the geometric angle between the anterior surface of the iris and cornea (synonyms: drainage angle; iridocorneal angle).

fluorescein angiography serial photography of the ocular fundus after intravenous administration of fluorescein solution. Used to characterize vascular disease of the retina, choroid, and optic nerve head.

fluorescein dye/stain a vital dye that fluoresces when stimulated with blue light. Used in many ophthalmic diagnostic tests, including the identification and characterization of corneal ulcers.

focus point of convergence of light rays. fovea retinal region of high visual acuity

in primates and birds.

fundus (ocular) the posterior portion of the eye visible through an ophthalmoscope, composed of the sclera, choroid, retina, and optic nerve head.

glands of Moll apocrine glands of the upper and lower eyelid margins.

glands of Zeis sebaceous glands of the upper and lower eyelid margins.

glaucoma ocular disease that may produce a syndrome of findings but that in domestic animals is uniformly characterized by increased intraocular pressure with resulting damage to the optic nerve. Categorized as primary glaucoma (occurring without preexisting ocular disease in an otherwise apparently healthy eye) or secondary glaucoma (glaucoma attributable to another ocular abnormality, such as lens luxation, intraocular tumor, anterior uveitis).

gonioscope specialized instrument for studying the iridocorneal angle.

gonioscopy examination of the iridocorneal angle with a goniolens, magnifying device, and light source.

granular iridica irregular cystic dilations on the pupillary margin of the iris in large herbivores. Most notable dorsally but typically also present ventrally. Also known as corpora nigra.

Haab’s striae linear gray-blue opacities deep within the cornea caused by fractures or stretching of Descemet’s membrane and development of fibrosis

and edema within the crack. Pathognomonic for glaucoma in most species; however, their significance in horses is not understood. Also called striate keratopathy.

haws syndrome bilateral condition in cats characterized by protrusion of the third eyelids without detectable cause. hemeralopia visual impairment/ blindness

in bright light (“day blindness”). hemianopia blindness involving one

half of the visual field. heterochromia iridis condition in which

the iris is not of uniform color or in which the right and left irides of one animal differ in color from each other. hippus spasmodic dilation and contraction of the pupil independent of stimu-

lation with light.

hordeolum localized, purulent infection of a gland of the eyelid. May be external (infection of the glands of Moll or Zeis; also known as stye) or internal (infection of the meibomian [tarsal] glands).

Horner’s syndrome set of ocular signs due to sympathetic denervation. May include miosis, ptosis, enophthalmos, and protrusion of the third eyelid.

hyalitis evidence of inflammation (usually white blood cells, inflammatory proteins/ debris, etc.) within the vitreous body; reflects inflammation of the surrounding tissues (ciliary body, retina, and choroid) rather than primary inflammation of the vitreous body itself (cf. aqueous flare).

hyalo-/hyaloid pertaining to the vitreous. hyperopia (hypermetropia) refractive

state of the eye in which the parallel rays of light would come to focus behind the retina if not intercepted by it (“farsightedness”). (See also myopia.)

hypertropia deviation of the eyes in which one eye is higher than the other. hyphema blood in the anterior chamber. hypopyon white blood cells in the

anterior chamber.

hypotony reduced intraocular pressure. image visual impression of an object

formed by a lens or mirror. In optics, a real image is an optical image that can be received on a screen. It is formed by the meeting of convergent rays of light, whereas a virtual image is an optical image that cannot be received on a screen. It is formed by diverging rays of light that appear to come from the image point but do not pass through it.

intraocular lens (IOL) artificial lens placed within the eye to correct

refractive error created by lens removal for cataract or lens dislocation.

intumescent lens a swollen or enlarged lens.

ipsilateral situated on or pertaining to the same side.

iridencleisis surgical procedure for glaucoma in which an incision is made at the limbus and the iris is incarcerated into the wound to create a filtering wick between the anterior chamber and the subconjunctival space. Performed rarely in domestic animals owing to the excessive inflammatory response in these species.

iridocorneal angle traditional outflow pathway by which aqueous humor exits the eye. It is bounded anteriorly by the peripheral cornea, posteriorly by the iris and ciliary muscles, internally by the pectinate ligaments, and externally by the sclera. The trabecular meshwork and ciliary cleft are contained within the iridocorneal angle. In some cases this term is used to refer to the geometric angle between the anterior surface of the iris and cornea (synonyms: filtration angle; drainage angle).

iridocyclitis inflammation of the iris (iritis) and ciliary body (cyclitis). Also called anterior uveitis.

iridodialysis separation of the base of the iris from the ciliary body; usually posttraumatic.

iridodonesis tremor or “fluttering” of the iris that occurs after loss of support due to luxation or removal of the lens. iridoplegia paralysis of the iris sphincter

muscle (i.e., mydriasis).

iris bombé adhesions (synechiae) between the pupillary margin of the iris and the anterior lens capsule due to anterior uveitis. The condition results in accumulation of aqueous humor in the posterior chamber, ballooning forward of the iris, and obstruction of the iridocorneal angle, which induces secondary glaucoma.

iris “freckle” lay term for iris nevus; a focal region of increased pigmentation of the iris.

iris prolapse protrusion of the iris through a perforating corneal or corneoscleral wound (cf. staphyloma).

iritis inflammation of the iris. keratectomy excision of part of the

cornea.

keratic precipitates (KPs) clumps of leukocytes and fibrin adhering to the corneal endothelium as a result of (and pathognomonic for) anterior uveitis.

keratitis inflammation of the cornea. Typically classified as ulcerative or nonulcerative.

keratitis nigrum see corneal sequestrum. kerato-/keratic pertaining to the cornea. keratoconjunctivitis simultaneous inflammation of the cornea and

conjunctiva.

keratoconjunctivitis sicca (KCS) inflammation of the cornea and conjunctiva secondary to dryness caused by impaired lacrimal gland function and decreased tear flow.

keratoconus enlargement of the cornea in which the cornea is protruded and conical.

keratoglobus enlargement of the cornea in which the cornea is protruded and globular.

keratomycosis keratitis caused by fungi. keratoplasty transplantation of a portion of the cornea. May be lamellar (replacement of only the deep or superficial layers) or penetrating (replacement of the entire depth of a corneal region; a

corneal graft).

lacrimation secretion of the precorneal tear film (tears).

lagophthalmos incomplete eyelid closure and globe coverage. Often associated with exposure keratitis.

lamina cribrosa fenestrated area of sclera approximately at the posterior pole of the globe, where optic nerve fibers exit the eye.

lens glass or other refractive material used to optically modify the path of light.

lens dislocation collective term for lens subluxation or luxation.

lens luxation disinsertion of lens zonules from the complete lens equator such that the lens luxates into the anterior chamber (anterior lens luxation) or into the vitreous cavity (posterior lens luxation).

lens subluxation disinsertion of lens zonules from the less than 100% of the lens equator such that the lens subluxates away from the region of disinsertion.

lenticonus abnormality of the lens characterized by a conical prominence on the anterior or posterior lens surface.

lentiglobus abnormality of the lens characterized by a spherical bulging of the anterior or posterior lens surface.

leukocoria literally, “white pupil.” Usually a sign of cataract, nuclear sclerosis, or retinal detachment.

leukoma notable corneal opacity; a less marked opacity is called a macula, and

the least dense opacity is termed a nebula. Adherent leukoma describes a corneal opacity in which the iris adheres to the endothelial surface.

limbus circular junction of the cornea and sclera.

macropalpebral fissure horizontally enlarged palpebral fissure due to excessive eyelid length (also known as euryblepharon).

macula moderate corneal opacity; a less marked opacity is called a nebula, and the most dense opacity is termed a leukoma. Alternative definition: a conerich area of high visual acuity in the primate retina that is devoid of blood vessels.

meibomian glands altered sebaceous glands located in the eyelids and opening onto the eyelid margin, producing the outer, oily layer of the tear film. Also known as tarsal glands.

menace response eyelid closure in response to a visually threatening movement.

microphakia abnormally small lens. microphthalmos/ia congenitally small

globe.

miosis constriction of the pupil (cf. mydriasis).

miotic pertaining to or characterized by constriction of the pupil (cf. mydriatic).

Mittendorf’s dot opacity of the posterior lens capsule at the posterior pole marking the embryologic site of hyaloid artery insertion.

“moon blindness” see equine recurrent uveitis (ERU).

morgagnian cataract a hypermature cataract in which the cortex is liquefied, permitting the lens nucleus to float or sink within the capsule.

mydriasis dilation of the pupil (cf. miosis).

mydriatic pertaining to or characterized by dilation of the pupil (cf. miotic). myopia refractive state of the eye in which

parallel rays of light come into focus in front of the retina (“nearsightedness”). (See also hyperopia.)

narrow-angle glaucoma glaucoma due to mechanical obstruction of the iridocorneal angle that limits aqueous humor from reaching the trabecular meshwork. Also known as closedangle or angle-closure glaucoma (cf. open-angle glaucoma).

nebula minor corneal opacity; a moderate opacity is called a macula, and the most dense scar is termed a leukoma.

neovascularization formation of new blood vessels where there were

GLOSSARY 459

previously none (as in cornea or on face of iris. (See also rubeosis iridis.) neurotrophic keratitis keratitis caused by dysfunction of cranial nerve V with

associated anesthesia of the cornea. nevus region of focally increased pig-

mentation, usually of the iris (lay term: “iris freckle”).

nodular granulomatous episclerokeratoconjunctivitis (NGE) a disease seen in many breeds but particularly rough collies and characterized by a tan-pink raised mass arising from the episclera (subconjunctiva) usually at the dorsolateral corneoscleral limbus, with adjacent conjunctival inflammation and often with corneal inflammation evident as corneal edema and corneal lipid degeneration. Suspected to be immune-mediated. Terminology is confusing but various synonyms have been used: nodular fasciitis, proliferative keratoconjunctivitis syndrome, fibrous histiocytoma, limbal granuloma, collie granuloma.

nyctalopia visual impairment/blindness in reduced illumination (“night blindness”).

nystagmus oscillatory movement of the eye. May be physiologic (optokinetic) or pathologic due to vestibular disease. Categorized as jerk nystagmus (having fast and slow phases), pendulous nystagmus (oscillations are approximately equal in deviation and speed; occurring in individuals in whom vision in both eyes has been defective since birth), and rotary nystagmus (the eye partially rotates around the visual axis; seen in central vestibular disease).

oculocardiac reflex vagally mediated decrease of heartbeat caused by pressure or traction on the eye; most notable with patient under general anesthesia and especially in horses and birds.

O.D. oculus dexter; the right eye. open-angle glaucoma glaucoma associ-

ated with a gonioscopically normal appearing drainage angle (cf. closedangle glaucoma, narrow-angle glaucoma).

ophthalmia neonatorum conjunctivitis in the newborn, especially behind closed lids of neonatal kittens and puppies with physiologic ankyloblepharon.

ophthalmoplegia paralysis of the ocular muscles. Further categorized as external (paralysis of the extraocular muscles; with strabismus) or internal (paralysis of the iris and ciliary body

muscles; with pupil dilation and loss of accommodation).

ophthalmoscope an instrument with a special illumination system for viewing the inner eye, particularly the retina and associated structures.

optic disc ophthalmoscopically visible portion of the optic nerve in the globe. Also called the optic nerve head and optic papilla.

optic disc cupping abnormal depression in the optic disc associated with glaucoma.

optic neuritis inflammation of the optic disc with decreased vision. Also called papillitis (cf. papilledema).

optic papilla ophthalmoscopically visible portion of the optic nerve in the globe. Also called optic nerve head.

O.S. oculus sinister; the left eye. O.U. oculi uterque; both eyes.

palpebral reflex eyelid closure in reaction to stimulation of the periocular skin.

pannus classically, nonspecific vascularization of avascular connective tissue (e.g., cartilage, cornea). However, the term is used commonly in ophthalmology to describe a characteristic immune-mediated disease of the cornea and conjunctiva of dogs. Synonyms include Uberreiter’s syndrome and chronic immune-mediated keratoconjunctivitis syndrome (CIKS).

panophthalmitis inflammation of all ocular and intraocular tissues, including the neural, uveal, and fibrous tunics of the eye, and often the orbital tissue as well (cf. endophthalmitis).

papilledema edema of the optic disc with normal vision (cf. optic neuritis). papillitis inflammation of the optic disc with decreased vision. Also called

optic neuritis (cf. papilledema). pectinate ligaments thin “fingers” of

anterior uveal tissue spanning from the iris root to the inner cornea/sclera across the iridocorneal angle.

“periodic ophthalmia” see equine recurrent uveitis (ERU).

peripheral anterior synechiae adhesions between the iris root and the peripheral cornea. May occur after unrelieved attacks of angle-closure glaucoma or chronic anterior uveitis (often seen only with gonioscopy).

persistent pupillary membranes (PPMs) congenital defect in which persistent strands of fetal vascular tissue extend from the iris collarette to other regions of the iris collarette (iris-to-iris PPMs), to the anterior lens capsule

(iris-to-lens PPMs), or to the corneal endothelium (iris-to-cornea PPMs).

Peter’s anomaly developmental defect in which ocular components surrounding the anterior chamber fail to cleave properly, resulting in anterior segment dysgenesis. Severity varies. May include adherent corneal leukoma, corneolenticular stalk, persistent pupillary membranes, cataract, and iridocorneal angle malformations with glaucoma.

photophobia ocular discomfort induced by bright light. (Because this is a symptom, not a clinical sign, it must be inferred in domestic animals.)

photopic pertaining to vision in bright ambient light; an eye that has become light-adapted.

photoreceptor specialized outer retinal cell (rod or a cone) that converts light to an electrical stimulus through phototransduction.

phthisis bulbi A small, shrunken, and deranged globe due to scarring secondary to (usually massive or chronic) intraocular inflammation.

plasmoid (secondary) aqueous proteinaceous aqueous resulting from leakage of plasma proteins into the aqueous humor across a disrupted bloodaqueous barrier. Pathognomonic for anterior uveitis.

polycoria occurrence of more than one pupil in the iris; classified as true polycoria if surrounded by sphincter muscle, and as pseudopolycoria if not. posterior chamber space into which the aqueous humor is first released bounded anteriorly by the posterior surface of the iris and posteriorly by

the anterior lens capsule.

posterior segment collective term for those parts of the eye posterior to the lens, including the vitreous, retina, choroid, optic nerve, and sclera (cf. anterior segment).

presbyopia refractive condition in which there is a diminished power of accommodation arising from impaired elasticity of the crystalline lens, as occurs with aging. progressive retinal atrophy (PRA) collective term for a series of inherited but rarely congenital progressive degenerative conditions affecting the neurosensory retina or retinal pigment epithelium and associated with impaired vision and, ultimately, blindness. Also known as progressive

retinal degeneration (PRD). proptosis forward displacement of the

globe (exophthalmos) such that

the globe equator protrudes beyond the eyelid margins as occurs during trauma, especially in brachycephalic dogs.

pseudopterygium region of bulbar conjunctiva that advances over but does not adhere to the cornea (cf. pterygium); seen most commonly in rabbits, in which it is also called corneal occlusion syndrome.

pterygium region of bulbar conjunctiva that advances onto and adheres to the cornea (cf. pseudopterygium).

ptosis drooping of the upper lid due to dysfunction of the oculomotor nerve (cranial nerve III), sympathetic denervation, or excessive weight of the upper eyelids.

pupil hole in the center of the iris that regulates light entering the posterior eye. Shape varies with species.

pupillary block blockage of the passage of aqueous through the pupil between the posterior and anterior chambers. Associated with some forms of glaucoma.

pupillary light reflex (PLR) constriction of the pupil when the retina of the same eye is stimulated with light (direct PLR) or when the retina of the opposite eye is stimulated (consensual PLR).

reflex involuntary, invariable, adaptive subcortical reaction to a stimulus. See also descriptions of corneal reflex, pupillary light reflex, palpebral reflex, and dazzle reflex (cf. response).

refraction the bending of rays of light that occurs as they pass from one transparent medium into another of different density, such as passage from air into the cornea, or from the aqueous humor into the lens.

response cortically mediated voluntary reaction to a stimulus that can be exaggerated or over-ridden and that may need to be learned so is not always present from birth. An example is the menace response (cf. reflex).

retina the innermost tunic of the eyeball, containing the neural elements for reception and transmission of visual stimuli.

retinal detachment separation of the neurosensory retina from the retinal pigment epithelium. Because this is an intraretinal breach, the term retinal separation is more strictly correct.

retinal dialysis tearing of the retina from its attachment at the ora ciliaris retinae or, less commonly, from the optic disc in association with retinal separation such that the retina is seen hanging from the optic nerve or ora ciliaris retinae (also called retinal disinsertion).

retinal disinsertion tearing and disinsertion of the retina from the ora ciliaris retinae in association with retinal separation such that the retina is seen hanging from the optic nerve or ora ciliaris retinae (also called retinal dialysis).

retinal dysplasia abnormal differentiation of retinal layers.

retinal pigment epithelial dystrophy collective term for a group of disorders in which retinal degeneration is accompanied by numerous, small, pigmentlike foci over the tapetal fundus. The primary defect is in the retinal pigment epithelium, whereas in generalized progressive retinal atrophy (PRA) the defect is in the photoreceptors. Also known as central progressive retinal atrophy.

retinal separation separation of the neurosensory retina from the retinal pigment epithelium. Sometimes less correctly called retinal detachment.

retinitis inflammation of the retina; usually caused by or causing associated choroiditis, resulting in the term chorioretinitis or retinochoroiditis, respectively. retinochoroiditis inflammation of the choroid and retina in which retinitis is the dominant and presumed initiating

factor (cf. chorioretinitis). retinopathy any disease condition of the

retina.

retinoschisis a congenital cleft of the retina; a cleavage of retinal layers. retrobulbar optic neuritis inflammation

of the optic nerve occurring without funduscopically visible involvement of the optic disc.

retroillumination use of light reflected from a deeper structure to examine a more anterior structure; for example, light reflected from the tapetum may be used to examine the clarity and position of the lens (cf. transillumination).

rod retinal photoreceptor adapted for vision in dim light and motion detection. Most domestic animal retinas are relatively rod-rich compared with the primate retina. (See also cone.)

rubeosis iridis neovascularization of the iris.

Sanson-Purkinje images series of images reflected from the surface of the cornea and the anterior and posterior lens capsules. Used to judge depth within the eye.

Schiøtz tonometer indentation tonometer for assessing intraocular pressure.

Schirmer tear test (STT) test for tear formation in which absorbent paper is

folded over the lid margin for 1 minute and the amount of wetting measured.

scleritis inflammation of the sclera. scotopic pertaining to vision in dim

ambient light or to an eye that has become dark-adapted.

sector iridectomy removal of an entire sector of iris extending from the pupillary margin to the root of the iris. Usually performed for tumor removal.

sequestrum see corneal sequestrum. slit-lamp biomicroscope microscope

for examining the eye, consisting of a binocular microscope with a movable light source that that can be changed in size, color, and focus.

spherophakia abnormally spherical lens. staphyloma protrusion of uveal tissue (iris or ciliary body) into a bulging area of cornea/sclera due to thinning (ectasia) or rupture of the wall of the eye. stars of Winslow multiple dark dots seen throughout the tapetal area of the fundus, which represent an end-on view of small choroidal vessels penetrating the tapetum to reach the outer retina. Most notable in herbivores

and cats.

strabismus condition in which the two eyes are not simultaneously directed at the same object in a coordinated fashion. Categorized as concomitant strabismus, in which the angle of deviation remains constant for all directions of gaze and with either eye fixating (typically without muscle paralysis), and nonconcomitant strabismus, in which the angle of deviation varies with the direction of the gaze or the eye that fixates (typically caused by paralysis or paresis of one or more extraocular muscles). Further categorized as convergent strabismus, in which the deviating eye turns inward (“cross-eyed”), and divergent strabismus, in which the deviating eye turns outward.

striate keratopathy linear gray-blue opacities deep within the cornea caused by fractures or stretching of Descemet’s membrane and development of fibrosis and edema within the crack. Pathognomonic for glaucoma in most species; however, their significance in horses is not understood (also called Haab’s striae).

stye localized, purulent infection of a gland of Zeis or Moll. Also known as an internal hordeolum. (See also hordeolum.)

swinging flashlight test observation of contralateral pupil size after light is

GLOSSARY 461

directed into the opposite eye. The result is positive when the contralateral pupil dilates as the light is diverted to it and is associated with a severe prechiasmal (retinal or prechiasmal optic nerve) lesion on that side.

symblepharon permanent adhesion between adjacent conjunctival surfaces or between cornea and conjunctiva.

synchysis scintillans cholesterol crystals in a liquefied vitreous body (cf. asteroid hyalosis).

syndrome a group of clinical signs that occur together; a disease or definite morbid process having a characteristic sequence of signs; may affect the whole body or any of its parts. Syndromes of importance in veterinary ophthalmology are listed in alphabetical order within this glossary.

synechiae adhesions between the iris and adjacent structures occurring as a result of anterior uveitis. Anterior synechiae occur between the iris and cornea. Posterior synechiae occur between the iris and anterior lens capsule (sing. synechia).

syneresis liquefaction of the vitreous body. May occur as a result of pathology or normal aging.

tapetum approximately semicircular, reflective layer of the choroid occupying up to the dorsal half of the fundus in many domestic species.

tarsal glands altered sebaceous glands located in the eyelids and opening onto the eyelid margin that produce the outer, oily layer of the tear film. Also known as meibomian glands.

tarsorrhaphy operation in which the lids are sutured together to reduce corneal exposure. May be temporary or permanent; partial or complete.

tear film break-up time (TFBUT) an assessment of precorneal tear film stability. In the presence of a normal lipid layer of the tear film, the TFBUT is a quantitative measure of mucin quantity and quality. Decreased mucin quantity or quality causes tear film instability and a shortening of the TFBUT.

Tenon’s capsule connective tissue sheath encircling the globe posterior to the limbus (also known as fascia bulbi).

Tenon’s space episcleral space between Tenon’s capsule and the globe.

therapeutic soft contact lens (TSCL) thin plastic lens that fits directly on the cornea under the eyelids, thereby providing corneal protection during healing.

tonography measurement of amount of fluid forced from the eye by constant pressure during a constant period. Used to assess the facility of aqueous outflow. Reduced in patients with glaucoma or a predisposition to glaucoma.

tonometer instrument for measuring the tone of the eye wall; used to estimate intraocular pressure. Categorized as applanation tonometer (instrument that estimates intraocular pressure by measuring the resistance of a specified area of cornea to being flattened or applanated; e.g., Tono-Pen), indentation tonometer (instrument that estimates intraocular pressure by measuring the resistance of the cornea and anterior chamber to being indented; e.g., Schiøtz tonometer), or induction-impact (or rebound) tonometer (instrument that estimates intraocular pressure by measuring the vibration of a plunger as it rebounds from the ocular surface; e.g., TonoVet).

transillumination examination of an ocular structure by use of a transversely directed beam of focal light; especially useful when the transilluminated structure is semitransparent and permits some light to pass through it (e.g., iris cyst) (cf. retroillumination).

trichiasis pathologic condition in which hairs from normal skin reach and irritate the corneoconjunctival surface (cf. distichiasis, ectopic cilia).

tumor a swelling or enlargement of varying size that may involve any structure; not necessarily neoplastic.

Uberreiter’s syndrome characteristic immune-mediated disease of the cornea and conjunctiva of dogs. Also known as chronic immune-mediated keratoconjunctivitis syndrome (CIKS), pannus, or chronic superficial keratitis (CSK).

uvea/uveal tract middle vascular tunic of the globe; consists of the iris and ciliary body anteriorly, and the choroid (including the tapetum) posteriorly.

uveitis inflammation of the iris, ciliary body, or choroid in any combination.

Termed anterior uveitis or iridocyclitis when the iris and/or ciliary body is involved; posterior uveitis when the choroid is involved; and panuveitis when all three are involved. Sometimes categorized by cause as endogenous (arising from causes within the body, such as neoplasia and infection) and exogenous (arising from causes outside the body, such as trauma).

uveodermatologic syndrome autoimmune destruction of melanocytes causing marked panuveitis, retinitis, and dermatitis seen in dogs. The human counterpart condition is Vogt- Koyanagi-Harada (VKH) syndrome.

versions simultaneous parallel movements of both eyes, such as eyes right, eyes left, eyes up, and eyes down.

viscoelastic material gel-like hyaluronic acid or methylcellulose derivative used to protect the corneal endothelium and inflate the anterior chamber during intraocular surgery.

vision faculty of seeing; sight. Requires functional eye and central nervous system, including visual (occipital) cortex. Can be further defined as binocular vision (image formed using both eyes synchronously), color vision (ability to distinguish subjectively a large variety of wavelengths of light in the visible spectrum), photopic vision (vision in bright illumination), and scotopic vision (vision in dim illumination).

visual acuity ability to distinguish shape and detail. This depends on the optical system of the eye (cornea, aqueous humor, lens, and vitreous), the sensitivity of the retina, and the interpretation of the images by the brain. Regions of higher visual acuity within the retina are usually associated with a greater density of cone photoreceptors and occur in species-dependent regions of the retina. (See also fovea, macula, and area centralis.)

visual-evoked potentials (VEPs) recording of electrical activity in the

central (retrobulbar) visual pathways after visual stimulation; used to assess the integrity and function of these pathways.

visual field extent of space that can be perceived when the head and eyes are kept fixed; the field may be monocular or binocular.

vitreous body transparent, colorless, gel-like mass between lens and retina. vitreous cavity space containing the vitreous body and bounded anteriorly by the posterior lens capsule and posteriorly by the inner limiting mem-

brane of the retina.

vitreous veils/plicae faint curtainlike opacities seen by focal light through a dilated pupil in the normal eye. The veils move gently in the vitreous when the eye moves.

Vogt-Koyanagi-Harada (VKH) syndrome autoimmune destruction of melanocytes causing marked panuveitis, retinitis, and dermatitis seen in humans. The term VKH-like or uveodermatologic syndrome is preferred for the similar syndrome in dogs.

Wood’s light light source equipped with a nickel oxide filter that produces ultraviolet light, used to stimulate fluorescence of fluorescein dye.

xeromycteria drying of the nasal mucosal surfaces as seen with neurogenic keratoconjunctivitis sicca.

xerophthalmia drying of the ocular surface tissues as seen with tear film abnormalities.

xerosis pathologic dryness of the conjunctiva, mucus membranes, or skin. xerostomia drying of the oral mucosal

surfaces, as seen with reduced salivation as in Sjögren’s syndrome.

zonules the numerous fine tissue strands (ligaments) that stretch from the ciliary processes to the lens equator for a full 360 degrees and hold the lens in place. zonulysis dissolution of the zonules, as with chymotrypsin, to facilitate intra-

capsular lens extraction.

A

Abducent nerve

anatomy and function of, 14, 318 strabismus due to lesions of, 332 testing of, 100

Abscess cerebral, 349

corneal, 191-192, 192f

retrobulbar, 360-361, 361f, 362f, 363f in rabbits, 428, 428f

subspectacular in snakes, 439, 439f Absolute glaucoma treatment, 253-254, 253b,

254f

Absorption maximum, 290, 293f Acariasis, 127t, 128t Accommodation, 5, 6f, 258, 260f, 435 Acetylcholine, 53b

Acyclovir, 45, 45t, 146 Adaptation in ocular injury, 63 Adenocarcinoma

third eyelid, 154, 155f uveal, 225, 225f

Adenoma

meibomian, 125, 125f uveal, 225, 225f

Adenovirus, canine, 144, 375-376, 377f Adhesion molecules

in inflammatory process, 67 in keratic precipitates, 79

Adhesives cyanoacrylate, 189 surgical, 56

Adnexa disease of

in rabbits, 429, 429f

systemic causes of in horses and cattle, 405t

nerve supply of, 13 Adrenaline, 53-54 Adrenergic agents, 53-54 Adrenergic antagonists, 54

Advancement conjunctival graft, 187, 187f, 188f

Advancement flap for eyelid reconstruction, 123, 124f

Age factors

in cataract formation, 267

in inherited retinopathies, 305-306 in intraocular pressure, 232

Agenesis, 63 Akabane virus, 409 Albendazole, 432

Albinism, ocular, 210, 211t Algae in uveitis, 214t

Allergic conjunctivitis, 137t, 147, 147f

Page numbers followed by f indicate figures; t, tables; b, boxes.

Allergic disorders of eyelid skin, 130t Allergy, food, eyelid skin disease due to, 130t Alopecia areata, 132t

Amblyopia, 266

Amelanotic leading edge of third eyelid, 152 Amikacin, 42, 185b

Aminoglycosides, 41-42 Amoxicillin, 40 Amphibians, 439-440, 440f

Amphotericin B, 44t, 45, 192t Ampicillin, 40

Analgesics for corneal ulcers, 186 Anaplasia in neoplasm, 78 Anemia, 396t

Anesthetics local, 55 topical

for injections, 36

for microbiologic samplings, 83-84 Angiography, fluorescein, 104, 105f Angiosarcoma, conjunctival, 150 Aniridia, 31, 209

Anophthalmos, 30 Anterior chamber

anatomy of, 17, 18f

embryonic and fetal development of, 28, 29f examination of, 88, 88f

shallow, in glaucoma, 236 Anterior segment

dysgenesis of, 210, 210f

examination of, 85-89, 85f, 86f, 87f, 88f Anterior uveitis, 213t

atropine for, 51-52 classification of, 215t defined, 69, 208

emergency treatment of, 425-426 systemic causes of, 401t

Antibiotics, 37-43, 37b. See Also specific types aminoglycosides, 41-42

azithromycin, 42 bacitracin, 42 cephalosporins, 40 chloramphenicol, 40 for conjunctivitis, 141

allergic, 147 viral, 146

for corneal lacerations, 424

for corneal ulcers, 184-186, 185b, 186 for equine recurrent uveitis, 221 fluoroquinolones, 42-43, 43t

for hordeolum and meibomian adenitis, 122, 122t

for ocular contusions and concussions, 423 penicillins, 38-40

polymyxin B, 42

selection and administration of, 37-38, 38t, 39t, 40t, 41t

sulfonamides, 42 tetracyclines, 42

Anticholinergic drugs, 51-53 Antifungals, 43-45, 44t Antiglaucoma drugs, 215-216 Antihistamines, 50, 141 Antihypertensive drugs, 397, 397t Antiinflammatory drugs. See Also

Corticosteroids for corneal ulcers, 186

for emergency treatment of ocular contusions and concussions, 423

nonsteroidal (See Nonsteroidal antiinflammatory drugs)

Antioxidants for cataracts, 269 Antiparasitic agents, 59 Antiseptics, 58

Antivirals, 45, 45t, 145-146 Aphakic crescent, 273, 273f Aplasia, 63

Applanation tonometry, 96-97, 96f Aqueous

loss of, necrosis and, 66 physiology of, 17-19, 18f, 18t

production and drainage of, 230-232, 231f, 232f

surgical procedures on, for glaucoma, 250-251, 251f

Aqueous compartment, 17, 18f Aqueous flare

corneal inflammation and, 68 detection of, 94-95, 94f, 95f histology, 79

in uveitis, 212

Aqueous humor misdirection syndrome, 282 Aqueous layer of precorneal tear film, 157

deficiency of, 166

Arrowhead procedure for lateral entropion, 118, 119f

Arterial blood pressure, normal, 397t Arterial circle of iris, 12

Arterial supply, 10-12, 12f Arteriography, orbital, 359, 361f Arteritis, equine viral, 400 Arthrogryposis-hydrencephaly, 409 Arthropods in skin disease of eyelid,

128t-129t Artificial tears, 56, 57t-58t A-scan ultrasound, 103, 104f Aspergillosis, 389t

Aspirin, 48, 49t, 219

Asteroid hyalosis, 281-282, 281f Astigmatism, 5, 6f

Astringents, 59

Atopic dermatitis, 130t

Atresia, congenital lacrimal, 162-163 Atrophy, 63, 64f

of iris, 63, 227-228, 228f optic, 298

retinal, 304, 381t, 402t in uveitis, 213