Pathology of the eye Flashcards
(115 cards)
1
Q
What are the parts of the outer tunic of the eye?
A
sclera and cornea
2
Q
What are the parts of the vascular tunic of the eye?
A
choroid, iris, and ciliary body
3
Q
What are the parts of the neural tunic?
A
the retina
4
Q
What is the area between the cornea and the sclera called?
A
the limbus
5
Q
When there is retinal separation, where does it occur?
A
in between the retina and the retinal pigment epithelium
6
Q
What type of cells does the retinal pigment epithelium interact with?
A
photoreceptors
7
Q
Describe the epithelium of the eye.
A
it is stratified squamous epithelium, highly organized, 5-6 layers, and does not keratinize
8
Q
Describe the stroma of the eye.
A
specialized type of fibrous connective tissue, much less fluid than other parts of the eye, composed of collagen
9
Q
What is Descemet’s membrane?
A
a thick basement membrane produced by corneal endothelium
10
Q
Where is Descemet’s membrane located?
A
in between the stroma and the corneal endothelium
11
Q
What is the purpose of the corneal endothelium?
A
it prevents the aqueous humor from leaking into the stroma
12
Q
What is the function of the pectinate ligament?
A
it allows aqueous humor to seep through
13
Q
What is the pectinate ligament connected to?
A
Descemet’s membrane
14
Q
Where is the tapetum lucidum located?
A
in the dorsal part of the retina
15
Q
Which layers of the retina is the tapetum lucidum located in between?
A
the choroid and the retinal pigment epithelium
16
Q
What is the difference between corneal erosion and corneal ulcers?
A
Corneal erosion is loss of epithelium down to the basement membrane and corneal ulcers go through the basement membrane
17
Q
What usually is the cause of corneal erosion?
A
trauma
18
Q
What are the causes ulcers?
A
trauma and certain bacteria and viruses
19
Q
What is a melting ulcer?
A
when bacteria complicate the ulcer by producing metalloproteinases that dissolve the cornea
20
Q
What is a descemetocele?
A
an ulcer that goes down into Descemet’s membrane
21
Q
How do you know if you have a desmetocele?
A
the ulcer becomes clear in the middle
22
Q
What is a perforated ulcer?
A
when the iris adheres to the ulcer
23
Q
Ulcers are usually associated with ________.
A
inflammation
24
Q
Where will exudate in ulcers come from?
A
the conjunctiva
25
How is erosion repaired?
epithelium looses up then the epithelium proliferates, slides onto the basement membrane and fills in
26
What can cause erosion to be recurrent?
if injury damages basement membrane then there are issues with attachment
27
What are the steps of ulcer repair?
epithelial proliferation, stromal neovascularization, and stromal fibrosis
28
Where does stromal neovascularization begin?
in the periphery at the limbus
29
What does ulcer repair create?
scar tissue
30
What is corneal edema?
fluid accumulation within the stroma due to the loss of epithelial or endothelial barrier
31
What causes corneal edema?
disruption of stromal fiber organization
32
What does corneal edema look like grossly?
a cloudy eye
33
What is the cause of chronic epithelial hyperplasia?
chronic persistent injury such as dry eye
34
What is another term for chronic epithelial hyperplasia?
epidermalization
35
What lesion does chronic epithelial hyperplasia cause?
rete ridge formation and keratinization
36
What is corneal neovascularization?
blood vessel ingrowth from the limbus into the peripheral stroma
37
What is stroma fibrosis?
the replacement of regular corneal fibrous stroma with scar tissue
38
What may stromal fibrosis resemble?
the dermis due to cutaneous metaplasia
39
What is inflammation of the cornea called?
keratitis
40
What types of exudate are associated with keratitis?
serous, fibrinous, purulent, and granulomatous
41
Where does exudate come from in keratitis?
conjunctiva, tears, and anterior uvea
42
Where does exudate accumulate in in keratitis?
epithelium, stroma, or adheres to the endothelium
43
What are keratitic precipitates?
when exudate from keratitis sticks on the endothelial side
44
What is feline corneal sequestration?
necrosis to the corneal stroma as the result of an ulcer; occurs at the base of the ulcer
45
How does feline corneal sequestration appear grossly?
as discrete brown focal discoloration
46
What is goniodysgenesis?
the incomplete or dysplastic development of the iridocorneal angle, pectinate ligament, and ciliary cleft
47
What can goniodysgenesis contribute to?
primary glaucoma
48
What is choroidal hypoplasia?
a thin choroid
49
What is choroidal hypoplasia associated with?
color-dilution mutant coat patterns
50
What is anterior uveitis?
inflammation to the iris and ciliary body
51
What is panuveitis?
inflammation to the iris, ciliary body, and choroid
52
What types of exudate is associated with uveal inflammation?
all types except catarrhal
53
In the case of uveal inflammatino, where does exudate that originates in the iris leak into?
the anterior chamber causing a hazy look in the eye
54
In the case of uveal inflammation, where does exudate leak to that originates in the choroid?
into the subretinal space
55
What causes uvual inflammation?
infectious agents, autoimmune, and phacoclastic uveitis
56
What is phacoclastic uveitis?
the lens ruptures and fibers enter into the eye
57
What is preiridial fibrovascular membrane?
PIFM! The proliferation of fibrovascular tissue on the anterior surface of the iris
58
Is PIFM acute or chronic?
chronic
59
What may PIFM result in?
anterior synechia, posterior synechia, closure of the iridocorneal angle, entropion uveae, and ectropion uveae
60
What is anterior synechia?
adhesion of the iris to the cornea
61
What is posterior synechia?
adhesion of the iris to the lens capsule
62
What can closure of the iridocorneal angle cause?
secondary glaucoma
63
What is entropion uveae?
inward contraction of pupillary margin
64
What is ectropion uveae?
outward contraction of the pupillary margin
65
What causes intra-ocular hemorrhage?
trauma, inflammation, hypertensive vasculopathy, and neoplasms
66
What may intra-ocular hemorrhage result in?
a detached retina
67
What are some common uveal neoplasms?
melanoma, ciliary body epithelial tumors, and lymphosarcoma
68
Where are uvual melanomas located?
in the anterior uvea and they do not usually spread past the eye
69
What parts of the uvea do lymphosarcomas usually include?
anterior uvea and choroid
70
What does retinal dysplasia cause?
wrinkles and folds rosettes
71
What causes retinal dysplasia?
genetic, viral infection during development
72
What is an example of a viral infection that causes retinal dysplasia?
bovine viral diarrhea
73
If there is inflammation in the retina is it usually exclusively in the retina?
no
74
What exudate types (infiltrates) are associated with retinal inflammation?
neutrophils, lymphocytes, macrophages, and PC (whatever that is)
75
What is degeneration/atrophy of the retina?
neuron loss from various layers depending on cause
76
What does degeneration/atrophy of the retina cause?
photoreceptor loss, collapse and gliosis
77
What causes retinal degeneration/atrophy?
ischemia, glaucoma, nutritional deficienccy, drugs, detachment, genetic, inflammation
78
When the retina detaches, what does it separate from?
the RPE
79
What results from retinal detachment?
hypertrophy of the RPE and loss of photoreceptors (long term result)
80
What causes retinal detachment?
hemorrhage, transudate from hypertensive vasculopathy, and exudate
81
What is microphakia?
a small underdeveloped lens
82
What causes Microphakia?
usually a congenital defect that is associated with other defects
83
Describe a cataract.
lens opacity due to disruption of fiber organization
84
What lens fiber changes occur in cataracts?
swelling, fragmentation, liquefaction, Morgagnian globules, mineralization
85
What causes cataracts?
congenital, aging, diabetes mellitus, and others
86
Where are cataracts located?
subscapular, anterior, and posterior
87
What is a hypermature cataract?
lens fibers liquefy and leak out; the lens collapses
88
What is nuclear sclerosis?
aging due to compression of nuclear lens fibers (there is constant re-epithelialization and the older fibers in the middle compress)
89
What is inflammation to the lens called?
phacitis
90
What is phacitis secondary to?
penetrating injury
91
What type of infiltrate is associated with phacitis?
pmns
92
What happens if the lens capsule ruptures due to phacitis?
it may cause phacoclastic uveitis
93
How does a luxated lens occur?
the zonules, the fibers that hold the lens in place, become ruptured
94
What happens to the lens when the lens is luxated?
it moves around; usually ventrally or anteriorly\
95
What happens if the luxated lens is lodged in the pupil?
a pupillary block
96
What is epithelial fibrous metaplasia secondary to?
rupture of the lens capsule
97
In cats, what occurs, potentially many years after, due to trauma to the lens?
trauma-induced-ocular sarcoma of cats
98
What is entropion?
the rolling in of the eyelid
99
What is ectropion?
the rolling out of the eyelid
100
What is inflammation of the eyelid called?
blepharitis
101
When the glands of the eyelid and the eyelid are involved, what is the inflammation called?
Meibomian adenitis
102
What is chalazion?
granulomatous inflammation of Meibomian glands and the eyelid
103
What neoplasms are associated with the eyelid?
melanoma, squamous cell carcinoma, meibomian gland tumors
104
What is inflammation of the conjunctiva and/or the third eyelid called?
conjunctivitis
105
What is pannus of the eye?
proliferation of fibrovascular tissue that grows onto the cornea; interface LP inflammation of the cornea
106
What neoplasms are associated with the conjunctiva?
squamous cell carcinoma
107
What is inflammation of the sclera called?
episcleritis
108
Describe episcleritis.
it is inflammation on the surface of the sclera and may extend into the 3rd eyelid
109
What are the two forms of episcleritis?
granulomatous form and necrotizing form
110
What is microphthalmia?
when the eye is small - there is a small underdeveloped globe
111
What is endophthalmitis?
the inflammation of all interior segments and chambers
112
What is panophthalmitis?
inflammation of all components of the eye
113
What is buphthalmos?
an enlarged globe
114
What is the cause of buphthalmos?
increased intraocular pressure secondary to glaucoma
115
What is phthisis bulbi?
atrophy of the globe - the eye was normal at one time but is not normal anymore
