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eyes and ears Flashcards

1
Q

absence of the eye

A

Anophthalmos

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2
Q

incomplete separation, or early fusion, of paired globes

A

Synopthalmia

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3
Q

– abnormally small eye

A

micropthalmia

– inherited defect in Collie dogs

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4
Q

inversion of the eyelids → trichiasis

A

Entropion

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5
Q

– eversion of the eyelids

A

ectropion

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6
Q

– rubbing of the eyelashes against the eye surface

A

Trichiasis

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7
Q

failure of complete fusion of the lips of the embryonic
choroid fissure

A

Coloboma

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8
Q

which part of the eye is most affected in coloboma

A
  • the posterior portions of the eye (optic disc, iris, ciliary body) most often affected
  • – inherited in Charolais cattle
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9
Q

what are the lesions of coloboma

A
  • cavitation of the choroid and sclera

– cavity lined by a thinned retinal layer

  • visual defects

– only in very severe cases

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10
Q

– etiopathogenesis Collie eye anomaly

A
  • improper development of the optic cup
  • abnormal formation of choroid and retina
  • chorioretinal dysplasia or choroidal hypoplasia
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11
Q

Collie eye anomaly lesions/defects:

A
  • abnormal retinal vessels
  • areas of chorioretinal dysplasia or hypoplasia
  • ectasia
               – optic disc
            – sclera
  • posterior staphyloma
  • ± severe visual impairment
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12
Q

sequela of collie eye anomali

A
  • retinal degeneration and detachment
  • intraocular hemorrhage
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13
Q

delayed or incomplete atrophy of the anterior
perilenticular vascular network results in

A

Persistent pupillary membrane

atrophy is frequently incomplete at birth

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14
Q

Persistent pupillary membrane lesions

A
  • bloodless strands

– short, threadlike protrusions from the area of
the minor arterial circle (iris collarette)

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15
Q

Persistent pupillary membrane clinical significance

A
  • obstructed vision
  • corneal or lens opacity

– due to dysplasia of corneal endothelium or lens
because of contact with the strands

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16
Q

Partial or complete absence of an eyelid

A

Eyelid agenesis and coloboma

partial defect (coloboma) involving the upper
eyelid is the most common
» localized corneal dessication followed by
cutaneous metaplasia

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17
Q

abnormal or prolonged fusion or adhesion of
the eyelids

A

Ankyloblepharon

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18
Q

what is the function of physiological Ankyloblepharon

A

essential to protect the immature cornea from
infectious keratitis, dessication, and corneal
rupture

Congenital ankyloblepharon in dogs and cats persists into the 2nd week of life

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19
Q

inward rolling of the eyelid margin (inversion or
infolding) because of inadequate overall length

A

Entropion

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20
Q

what is the sequela of entropion

A

irritation of the cornea by the eyelid skin,
cilia, and/or hair

very common anomaly in purebred dogs

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21
Q

undue laxity of an excessively long
eyelid resulting in an outward gaping of the
eyelid margin

A

ectropion

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22
Q

what is the sequela of ectropion

A

chronic conjunctivitis and keratitis from
exposure to debris

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23
Q

presence of an ectopic row of cilia originating
from the ducts of the Meibomian glands

A

Distichiasis

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24
Q

what is sequela of Distichiasis

A

corneal ulceration

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25
Q

misdirection of the normal cilia

A

Trichiasis

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26
Q

what is the sequela of trichiasis

A

corneal irritation leading to keratitis and even
ulceration

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27
Q

abnormally placed cilia within the lamina propria
of the conjunctiva

A

ectopic cilia

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28
Q

what is the sequela of ectopic cilia

A

their emergence through the palpebral
conjunctiva can cause severe corneal irritation

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29
Q

suppurative adenitis of the adnexal glands
of Moll or Zeis

A

external Hordeolum (stye)

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30
Q

suppurative adenitis of the Meibomian
gland

A

internal Hordeolum (stye)

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31
Q

pathogenesis of internal focal hordeolum

A

persistent inflammation >> sebaceous
secretions extend into the adjacent soft
tissues >> granulomatous response

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32
Q

differential diagnosis for focal hordeolum

A

adenoma
» fungal granuloma
» lymphoid hyperplasia

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33
Q

sterile granulomatous inflammation of the
Meibomian gland

A

Focal Chalazion

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34
Q

differential diagnosis of chalazion

A

Meibomian gland adenomas

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35
Q

Diffuse blepharitis Types

A

ulcerative,

seborrheic

, allergic

, actinic,
parasitic

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36
Q

a shetland is presented wih erythema,crusting, vesiculation, and erosion of the dorsum of the nose,inner aspect of the pinna, perioral and periocular region. which diases do you suspect

A

diffuse Blepharitis

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37
Q
  • most common tumor of canine eyelid (80% of all eyelid tumors)
A

Meibomian gland adenoma

it is the exact counterpart of sebaceous adenomas

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38
Q

2nd most common tumor of the canine eyelid

A

melanocytoma

universally benign

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39
Q

in which dog breeds are dermoids found

A

: St. Bernard, Dalmatian

– lateral canthus or limbus

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40
Q

benign, raised, wedge-shaped growth of the
conjunctiva

A

Pterygium

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41
Q

what causes Pterygium (conjuctival disease)

A
  1. trauma
  2. irritation
  3. allergens like pollen
  4. toxins
  5. infections>bacteria, virus,mycobacterium, parasites
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42
Q

failure of in growth of the future iris epithelium

A

iris hypoplasia

more frequent in horses; inherited

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43
Q

Choroidal hypoplasia associated with

A

inadequate pigmentation of the retinal pigment
epithelium and choroids
– CEA

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44
Q

posterior uveitis or choroiditis

A

inflammation of ciliary body and choroid

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45
Q

inflamamtion of iris and ciliary body

A

anterior uvitis or iridocyclitis

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46
Q

what causes conjuctivitis

A

can be associated with inflammation elsewhere, e.g., upper respiratory disease with concurrent keratoconjunctivitis

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47
Q

neoplasms of the conjuctiva are common in which animals

A

cattle followed by horses, dogs and horses

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48
Q

which conjuctival tumer is common in cattle

A

SCC

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49
Q

.SCC Predisposing factors include

A
  • actinic iradiattion and hypomelanosis
  • associated with IBR virus
  • genetic predisposition in herefords
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50
Q

A horse present with begin mass at the limbal region or the leading edge of the 3rd eyelid that progress to the conjunctiva.which tumer do you suspect?

A

SCC of the conjuctiva

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51
Q

a faint loss of transparency of cornea that can be seen with oblique illumination

A

nebulla

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52
Q

a light gray spot in the cornea that can be visualized in natural light

A

macula

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53
Q

any dense white spot that may indicate moderate to severe corneal disease

A

Leukoma

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54
Q

gray-blue opacity of the cornea and may have a “cobblestone” appearance.

A

corneal edema

55
Q

what causes superficial keratitis

A

: due to corneal ulceration (ulcerative keratitis)

56
Q

what causes deep keratitis

A

: due to infection (mycotic or bacterial) or intraocular inflammation

57
Q

stereotyped sequence of keratitis

A

1) edema
2) leukocyte immigration from tears and distant limbic venules
3) corneal stromal vascularization
4) fibrosis
5) epithelial metaplasia with pigmentation

58
Q

discribe the epithelial type of keratitis

A
  • usually transient and mild non ulcerative keratitis
  • superficial punctate keratitis consists of multiple fine epithelial opacities that are foci of epithelial hydropic change
  • intercellular fluid accumulation (bullous keratopathy) is seen as a sequel to corneal edema
59
Q

describe Stromal keratitis

A
  • it is a non ulcerative keratitis which can either be deep or superficial
60
Q

are are the two types of non ulcerative keratitis

A

epithelial and stromal keratitis

61
Q

describe the etiopathogenesis of ulcerative keratitis

A
  • loss of epithelium initiates a series of reactions caused by tear imbibition,
  • local production of cytokines
  • opportunistic microbial contamination of the wound
62
Q

sequela of ulcerative keratitis

A
  • involve cornea, conjunctiva, and uvea
  • the ulcer may:
             1. heal with vascularization and scarring;                           granulation tissue fills the ulcerative defect.
         2. persist as a stubborn but nonprogressive lesion          3. progress to involve more of the stroma and epithelium
  • stromal liquefaction that reaches the Descemet’s membrane results in its forward bulging as a descemetocele or keratocele due to increased intraocular pressure; this appears grossly as a transparent center to the ulcer
63
Q

focal adhersion of the iris to the injured cornea due to anterior uvitis is called

A

anterior synechia

64
Q

WHAT PREDISPOSE THE CORNEA TO ANTERIOR synechia

A
  • the Descemet’s membrane, although resistant to penetration of microbial agents themselvesis permeable to inflammatory mediators and microbial toxins which diffuse into the anterior chamber;
  • these chemicals, combined with a vasoactive sensory neural reflex from irritated cornea, are responsible for the vasodilation and exudation in anterior uvea

e) the anterior uveitis may result in sufficient fibrin exudation so as to predispose to focal adhesions

65
Q

a fibrous tunic (i.e., corneal) defect lined by uvea (i.e., iris) or incorporation of the iris into the corneal stroma

A

anterior staphyloma

it is a a permanent anterior synechia

66
Q

what causes anterior staphyloma

A

in the case of corneal perforation, the iris flows forward to plug the defect and subsequently becomes incorporated into the corneal scarring, this defect is a permanent anterior synechia

67
Q

potrution of the descemet’se membrane through an ulcerated membrane

A

: descemetocele

68
Q

anterior synechia (iris adhering to the cornea) lined by epithelial cells

A

corneal fistula

69
Q

discuss the summary flow chart for ulcerative keratitis

A
70
Q

diffuse, blue-gray clouding of the cornea associated with inflammatory changes in the deep corneal layers

A

stromal (interstitial) keratitis caused by iridocyclitis

is characterized by deep vascularization, i.e., ingrowth of vessels (usually short and straight) from the ciliary body.

71
Q

pannus keratitis

A
  • it is a type of superficial stromal keratitis
  • seen mostly in GSD
  • chronic, nonulcerative proliferative inflammation
  • there is no ulceration but pigmentation is often marked
72
Q

pathogenesis of pannus keratitis( superficial stromal keratitis)

A
  • immune-mediated; cell mediated injury to altered corneal antigens following prolonged exposure to UV light;
  • severity is exacerbated by dust and high altitudes
73
Q

what are the lesions of pannus keratitis( superficial stromal keratitis)

A
  • vascularized opacity in the corneal stroma (bilateral);
  • marked pigmentation which eventually infiltrates the entire corne
  • a converting the superficial stroma to an opaque membrane resembling granulation tissue;
  • histologically, there is an intense mononuclear inflammatory infiltrate
74
Q

what are the gross lesions of eosinophilic keratitis

A
  • . predominantly in cats, occasionally in horses
  • . grossly, granular white proliferative lesion extending inwardly along what seems to be the corneal surface from the medial or lateral limbus
  • microscopically, infiltration of eosinophils, plasma cells, mast cells, and macrophages
  1. etiopathogenesis is unknown
75
Q

what causes deep stromal keratitis

A

a) results from extension from anterior uveitis or from endothelial damage by uveitis, trauma, or glaucoma
b) common in horses which have suffered one or more bouts of equine recurrent ophthalmitis

76
Q

what causes Keratoconjunctivitis sicca, KCS

A

2) decreased lacrimal secretion which normally has protective lubricant and bacteriostatic functions in the conjunctival sac

common in toy breeds

77
Q

what is a sequela of keratoconjuctivity sicca

A
  • chronic keratoconjunctivitis with congestion,
  • epithelial keratinization,
  • dry lusterless cornea and a thick, white, sticky, ropy mucoid exudates
  • . Chronic corneal changes may include ulceration, melanosis and lipoidal dystrophy.
78
Q

summary: Non-ulcerative keratitis (followed by iridocyclitis)

A
79
Q

what are the lesons of iridocyclitis

A
  • marked hyperemia/congestion of iridal and ciliary vessels

–altered formation of aqueous

  • reflected by a drop in intraocular pressure

–exudation

  • cellular (mononuclear or neutrophils)

•±exudation of fibrin

80
Q

what is aqueous flare

A

lesion of iridocyclitis (antirior uvitis) characterised by accumulation of exudate (fibrin and inflammatory cells) in the aqueous

81
Q

yellow-white or pink flocculant sediment in the anterior chamber

A

hypopyon

a iridocyclitis lesion

82
Q

• blood or neutrophils in the anterior chamber

A

hyphema

it is aIridocyclitis (anterior uveitis)

83
Q

stippled appearance of the cornea with adherance of clumps of inflammatory cells to the posterior surface of the cornea

A

keratitis punctata

a lesion of anterior uvitis

84
Q

“mutton-fat” keratic precipitates characteristics

A

Iridocyclitis (anterior uveitis) lesions:

  • white, yellowish greasy precipitates of inflammatory cells (granulomatous response)
  • adherent to the corneal endothelium
85
Q

sequela of Iridocyclitis (anterior uveitis)

A
  • glaucoma (increased intraocular pressure)
  • lens luxation
86
Q

Iridocyclitis (anterior uveitis) pathogenesis and types

A
  • fibrinous exudation over the iris
  1. anterior synechia (adhesion of iris to cornea)
  2. posterior synechia (adhesion of iris to lens)
  • partial synechia → small visual defects
  • total synechiae→ blockage of aqueous flow and glaucoma
87
Q

iris bombé

A

sequela to Iridocyclitis (anterior uveitis)

360 ° (complete) posterior synechiae
• bowing of the iris
anteriorly

  • apposition of the iris to the lens preventing aquous from flowing from the posteria to the anteria chamber.pressure rises resulting in bowing of the iris
88
Q

occlusio pupillae

A

a complete fibrovascular membrane across the pupil

fibrovascular membrane on the iris face → pupillary
block → neovascular glaucoma

it is a sequela to iridocyclitis

89
Q

eversion of the pigmented posterior epithelium of the iris at
the pupillary margin

A

Ectropion uveae

90
Q

discuss changes that can conceal changese of iridocyclitis deep in the eye

A

the blue-gray corneal opacity due to edema, interstitial
keratitis and fibrosis

– examples:

  • in MCF of cattle

– iridocyclitis with hypopyon may be obscured by
the onset of interstitial keratitis

  • dogs recovering from ICH

– iridocyclitis due to type III hypersensitivity

91
Q

significance effect of uveitis on cornea

A

edema and hyperemia due to endothelial damage

(as in ICH, FIP)

92
Q

effects of uveitis on cornea

look at the picture

A
  • stromal fibrosis
  • vascularization
93
Q

discuss the effect of uvitis shown below

A

corneal ullceration

94
Q

bullous keratopathy

A

edema due to percolation of stromal fluid into
the corneal epithelium

95
Q

hypotonic, shrunken, disorganized eye

A

phthisis bulbi

96
Q

lesions of Choroiditis (posterior uveitis)

A
  • marked exudation
  • choroid
  • vitreous
  • retinal detachment

• local or general

  • retinal degeneration

• esp. horses (no retinal arteries)

  • atrophy/proliferation of choroidal pigment cells
97
Q

which parts of the eye are affected by the equine recurent uvitis

A
  • damage to the choroid, retina and optic nerve

leading to blindness

98
Q

etiopathogenesis of equine recurent uvitis

A
  • immunologic reaction against intraocular leptospiral antigens
                    – a delayed reaction to a systemic infection                      with Leptospira interrogans serovar pomona
  • intraocular dead or dying microfilaria of

Onchocerca cervicalis act as antigens

  • deficiencies of vitamins A, B2

(riboflavin) and C
have been incriminated but not proven

99
Q

lesions of equine recurent uvitis

A

anterior neutrophilic uveitis
which rapidly becomes predominantly lymphocytic

100
Q

diagnoses of equine recurent uvitis

A

presence of an eosinophilic hyaline membrane
within the apical cytoplasm of the nonpigmented
ciliary epithelium and resembles amyloid

101
Q

sequelae of equine recurrent uveitis

A
  • interstitial keratitis
  • cataract
  • lens luxation
  • synechiae
  • retinal separation
102
Q

what causes glaucoma

A
  • sustained increased in intraocular pressure due to

– decreased drainage of aqueous humor
– increased production of aqueous

103
Q

glaucoma is predisposed by

A
  • ocular disease
  • uveitis + synechiae
104
Q

what cuases Congenital glaucoma

A

abnormal development of anterior chamber

105
Q

what causes primary glacoma

A

malformation of filtration angle

inherited, bilateral disease

breed predisposition: cocker spaniels

usually no ocular disease

106
Q

what are the lexamples of primary glaucoma

A
  • goniodysgenesis
     – detectable maldevelopment of the trabecular                        meshwork

      » incomplete remodeling of the solid mass of                           anterior chamber mesenchyme
  • open-angle glaucoma
         – no primary histologic lesions

       » no visible abnormality in the structure of the                           trabecular meshwork or other portions of the                         aqueous outflow pathways
107
Q

what causes secondary glaucoma

A

due to anything capable of obstructing the flow of
aqueous through the pupil (pupillary block)
or
– its exit through the trabecular meshwork (trabecular
occlusion)

108
Q

discuss eye lesions than can cause secondary glaucoma

A
  • inflammatory» synechiae, iritis, iridocyclitis, corneal ulcer
  • degenerative
  • neoplastic (uveal melanoma, lymphosarcoma)
  • occlusive

» pannus, inflammatory debris, tumor cells
» lens (luxation, intumescent cataract)

109
Q

buphthalmos

A

Glaucoma lesions/sequelae:

  • enlarged globe,
  • thinning of the sclera
110
Q

lesions of glaucoma on the cornea

A

chemosis
• pannus
• dessication
• ulceration

111
Q

lesions of glaucoma on the lens

A
  • cataract
  • subluxation/luxation
112
Q

what are the effects of glaucoma on the uvea

A
  • uveal tract reaction
  • atrophy and scarring
113
Q

lesions of glaucoma on the retina

A
  • retinal degeneration

• ganglion cell layer, inner nuclear layer

114
Q

effects of glaucoma on the optic nerve

A

degeneration of branches of optic nerve and the optic
disc (cupping of the optic disc)
– blindness

115
Q

faulty differentiation of the retina (photoreceptor cells)
with proliferation of one or more of its constituents

A

Retinal dysplasia

116
Q

what are the lesions of retinal dysplasia

A

lesions are characterized by rosettes composed of a
variable number of neuronal retinal cells, often with
accompanying retinal folds

117
Q

retinal dysplasia is associated with……..

A
  • a single ocular defect or
  • multiple ocular anomalies

– microphthalmia
– posterior coloboma

118
Q

what causes secondary retinal dysplasia

A
  • in utero viral infections

BVD in calves, bluetongue in lambs

  • vitamin A deficiency
  • x-ray irradiation
  • certain drugs
  • intrauterine trauma
119
Q

Retinal dysplasia lesions

A
  • rosettes with primitive, undifferentiated neuronal cells
    • retinal folds
120
Q

retinal dysplasia lesions on anterior segment of the eye

A
  • corneal scar
  • hypoplastic iris
  • cataractous lens
  • dysplastic retina
121
Q

what causes renitis

A
  • systemic infections which attack nervous tissue

• canine distemper

  • neuronal degeneration with gliosis

• MCF, FIP

  • ocular toxoplasmosis

– choroidal infections

  • toxoplasmosis
  • tuberculosis
122
Q

loss of photoreceptors and other retinal neurons with formation of spaces within the retina

A

retinal degeneration

there is decreased thickness of the neurosensory retina
(retinal atrophy)

123
Q

causes of retinal degeneration

A
  • 2° to retinitis or chorioretinitis

– senility

  • focal retinal degeneration
  • nutritional deficiency
           vitamins A, E, taurine
  • toxicity
    - pressure atrophy due to glaucoma

– excessive exposure to light
– hypertension
– irradiation
– infectious agents
– hereditary (most important in dogs)

124
Q

what are the characteristics of generalised Progressive retinal atrophy (PRA)

A
  • early onset
  • photoreceptor dysplasia
125
Q

what are the lesions of central Progressive retinal atrophy (PRA)

A

later onset
• retinal pigment epithelium dystrophy →
photoreceptor degeneration

126
Q

discuss etiopathogenesis of retinal degeneration

A
  • photoreceptor dysplasia
  • it is nherited in Irish setters, miniature and toy poodles, cockerspaniels, etc.
  • photoreceptors never reach morphologic or physiologic maturity
  • with time, photoreceptor loss extends to 2° atrophy of nuclear and plexiform layers of the retina
127
Q

what are the lesions of generalised progressive retinal atrophy (PRA)

A
  • rods affected first

degeneration of the processes and cell bodies in
the outer nuclear layer this results in poor dim- light vision or night blindness

  • involvement of the cones→loss of day vision
  • degeneration of RPE, disappearance of retinal vessels leading to total blindness
  • progressive loss of the inner nuclear layer
  • degeneration of the pigment epithelium
  • narrowing and disappearance of the retinal vessels leading to total blindness
128
Q

what is the effect of generalised PRA on the rods

A
  • degeneration of the processes and cell bodies in the outer nuclear layer
  • resulting in poor dim-light vision or night blindness
129
Q

what are the effects of generalised PRA on the cones

A

loss of day vision

130
Q

discuss the lesions seen below

A
  • Retinal degeneration
  • hyper-reflectivity of the tapetal retina dorsal to the disc
  • narrowing of the retinal vessels
  • pallor to the optic disc
131
Q

discuss the cause of central progressive retinal atrophy

A
  • inherited in collies, labradors and English springers
132
Q

what is the primary lesion of central progressive retnal atrophy

A

primary pigment epithelial dystrophy

133
Q

DISCUSS THE PATHOGENESIS FOR CENTRAL PRA

A
  • normally RPE engulfs and degrades shed photoreceptor outer segments by intracellular phagocytosis resulting in a gradual buildup of intracellular lipopigments throughout life

– abnormally
• defective intracellular phagocytosis of shed
photoreceptor outer segments → excessive
membrane peroxidation → lipopigments thus
accumulate to excess in the RPE

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