Chapter 29: The Eye Flashcards
1
Q
Many blinding conditions that result from pathologic angiogenesis (i.e., corneal neovascularization and diabetic retinopathy) can be sucessfull treated using what?
A
VEGF antagonists
2
Q
Proptosis of the eye is representative of which kind of lesions within the orbit?
A
Space-occupying lesions
3
Q
Enlargement of the lacrimal gland from inflammation or neoplasm produces proptosis which displaces the eye in which direction?
A
Inferiorly and medially
4
Q
What are the 2 most common primary tumors of the optic nerve and what type of proptosis do they produce?
A
- Gliomas (especially pilocytic astrocytomas) and Meningiomas
- Axial proptosis (eye bulges straight forward)
5
Q
Axial proptosis is an important clinical manifestation of which thyroid disorder?
A
- Graves disease —> Exophthalmos
- Enargement of the extra-ocular muscles w/ increased glycosaminoglycans
6
Q
Uncontrolled sinus infections may spread to the orbit as an acute bacterial infection, this occurs most commonly in which patients?
A
Immunosuppressed or DKA (mucormycosis!)
7
Q
________-related disease should be excluded before declaring an orbital inflammation to be idiopathic
A
IgG4-related disease
8
Q
The presence of necrosis and degenerating collagen along with vasculitis in orbital inflammation should raise the suspicion of which disease?
A
Wegener granulomatosis
9
Q
Idiopathic orbital inflammation is characterized histologically by?
A
Chronic inflammation and variable degrees of fibrosis
10
Q
Which immune cells are typically part of the inflammatory infiltrate associted with idiopathic orbital inflammation?
A
Lymphocytes and plasma cells; occasionally eosinophils
11
Q
What is the origin of the most frequently encountered primary neoplasms of the orbit?
A
Vascular in origin (capillary hemangioma of infancy and early adulthood, lymphangioma (children), and cavernous hemangioma (adults))
12
Q
Which 4 orbital masses are encapsulated?
A
1) Cavernous hemangioma
2) Pleomorphic adenoma of the lacrimal gland
3) Dermoid cyst
4) Neurilemmoma
13
Q
Drainage system of the sebaceous gland obstructed at the eyelid margin is called?
A
Blepharitis
14
Q
What is the most common malignancy of the eyelid?
A
Basal cell carcinoma
15
Q
Basal cell carcinoma tends to more commonly affect which 2 areas of the eyelid?
A
- Lower eyelid
- Medial canthus
16
Q
When lipid extravasates into surrounding tissue and provokes a granulomatous response producing a lipogranuloma in the eyelid, this is known as?
A
Chalazion
17
Q
Sebaceous carcinoma of the eyelid has a predilection for ______ spread and tends to spread first to the _______ and _______ nodes
A
Sebaceous carcinoma of the eyelid has a predilection for intraepithelial spread and tends to spread first to the submandibular and parotid nodes
18
Q
What are the morphological characteristics of a basal cell carcinoma of the eyelid?
A
- Pearly nodules, telangiectatic vessles, central ulcer (“rodent ulcer”), rolled edges
- Peripheral palisading
*Pearly w/ depressed central area
19
Q
Sebaceous carcinoma of the eyelide is most commonly seen in which gender/age?
What ethnicity is at higher risk?
A
- Woman >40 yo
- Asians
20
Q
_______ spread of sebaceous carcinomas may mimic Bowenoid actinic keratosis in the eyelid and carcinoma in situ in the conjunctiva
A
Pagetoid
21
Q
What is the morphology of the neoplastic cell cytoplasms seen in sebaceous carcinoma of the eyelid?
A
“Foamy” cytoplasm
22
Q
Which stain is considered the best for the diagnosis of sebaceous carcinomas of the eyelid?
A
Oil-Red-O staining of fresh-frozen tissue
23
Q
Which tumor is seen in the eyes of AIDS patients and if present in the eyelid appears purple, but will appear bright red if in the conjunctiva?
A
Kaposi Sarcoma
24
Q
Granulomas associated with systemic sarcoidosis may be detected in which part of the conjunctiva?
A
Conjunctival fornix
25
Primary lymphoma of the conjunctiva is most likely to develop in what part?
Fornix
26
Infection by which organism may produce significant conjunctival scarring?
*Chlamydia trachomatis* *(trachoma)*
27
Dry eyes (xeropthalmia) results from a deficiency in the aqueous component of the tear film generated by?
Accessory lacrimal glands embedded within the eyelid and fornix
28
A reduction in the number of which cells associated with the conjunctiva leads to a decrease in surface mucin, which is essential for the adherence of the aqueous components of tears to the corneal epithelium?
Goblet Cells
29
Submucosal growth of fibrovascular CT that migrates onto the cornea in a winglike fashion is known as?
Pterygium
30
A small, yellowish submucosal elevation appearing astride the limbus, but not invading the cornea, is known as what?
Pinguecula
31
Pterygium and Pinguecula are a result of what?
Sun exposure (actinic damage)
32
Squamous papilloma and conjunctival intraepithelial neoplasia may be associated with the presence of which virus?
HPV types 16 and 18
33
What is the significance of Mucoepidermoid Carcinomas of the conjunctiva?
Follow an **aggressive** course
34
Squamous neoplasms and melanocytic neoplasms and their precursors tend to develop at which part of the conjunctiva?
Limbus
35
Pigmented lesions (nevi) of the conjunctiva most likely represent?
Melanomas or melanoma precursors
36
Conjunctival melanomas typically develop through a phase of intraepithelial growth termed?
Primary acquired melanosis with atypia
37
What is the most common primary intraocular tumor in adults?
Uveal melanoma
38
Where s the first evidence of metastasis of uveal melanomas typically seen due to its almost exclusively hematogenous spread?
Liver
39
What are the 2 oncogenes associated with Uveal Melanomas?
GNAQ and GNA11
40
Which conditions may give the sclera a "blue" appearance?
- Following episodes of scleritis may become thin, **brown color turns blue** from the **Tyndall effect**
- Thinned in eyes with **high intraocular pressure**; lesion known as *staphyloma*
- Osteogenesis imperfecta
- Due to heavily pigmented congenital nevus of underlying uvea, condition known as *congenital melanosis oculi;* accompanied by periocular cutaneous pigmentation is known as *nevus of Ota*
41
What makes up the major refractive surface of the eye?
Cornea and overlying tear film - **not the lens**
42
What is Myopia and why does it develop?
- Short-sightedness -- can see near, trouble seeing far
- Images falls in **front** of the retina
- Eye is too long for its refractive power
43
What is Hyperopia and why does it develop?
- Far-sightedness -- can see far, trouble seeing near
- Image falls **behind** the retina
- Eye that is too short for its refractive power
44
Which stain is used to highlight the basement membrane of the cornea?
PAS
45
Which features of the cornea contribute to high rates of success with corneal transplantation?
**Lacks** blood vessesl and lymphatics
46
Risk of corneal graft rejection increases with what?
What type of graft rejection is most common?
- Increases w/ **stromal vascularization**, inflammation and invasion
- **Non**-immunologic graft rejection = **more common**
47
Corneal vascularization may accompany what pathologies and how can it be treated?
- Corneal edema, inflammation, and scarring
- VEGF antagonists
48
The corneal endothelium is derived from which primitive cell lineage?
What does it rest on?
- Neural crest cells
- Corneal endothelium rests on its basement membrane, **Descemet mebrane**
49
What is the site of copper deposition in the Kayser-Fleischer ring of Wilson disease?
Descemet membrane (corneal basement membrane)
50
Infection with which bacteria may cause corneal ulceration (keratitis)?
- *Staphylococcus aureus*
- *Streptococcus pneumoniae*
- *Pseudomonas aeruginosa*
- *Enterobacteriacea*
51
Which viruses and protozoa can cause corneal ulceration (keratitis)?
- Herpes simplex and herpes zoster
- *Acanthamoeba*
52
Chronic herpes simplex keratitis is associated with what morphological finding in the cornea?
- Granulomatous reaction involving the Descemet membrane
- Infected cells may coalesce to form multinucleated giant cells
53
In keratitis, dissolution of the corneal stroma may be accelerated how?
Activation of **collagenases** within corneal epithelium and **stromal fibroblasts** (aka keratocytes)
54
What is the pattern of injury of corneal degenerations and are the familial?
- Can be **unilateral** and **bilateral**
- Typically **nonfamilial**
55
What is the pattern of injury of corneal dystrophies and are they familial?
- Typically **bilateral**
- **Hereditary**
56
What occurs in Calcific band keratopathy?
May complicate what condition?
- Deposition of **calcium** in the **Bowman layer = Corneal degeneration**
- May complicate **chronic uveitis,** especially in **chronic juveline rheumatoid arthritis**
57
Actinic band keratopathy develops as a result of what?
What is seen in this condition?
- People exposed **chronically** to **high levels of UV light**
- **Horizontal band of solar elastosis** in superficial layers of corneal collagen ---\> **corneal degradation**
58
What is Keratoconus and why is it unique?
What does it result in?
- Progressive thinning and ectasia of the cornea **w/o** evidence of inflammation or vascularization
- Results in a cornea that has a **conical** rather than **spherical** shape --\> **irregular astigmatism**
- Unique because unlike other degenerations is typically **bilateral**
59
What conditions is the development of Keratoconus associated with?
- Marfan syndrome and Down syndrome
- May develop from genetic predisposition superimposed by an enviornmental insult, such as **eye rubbing in response to atopic conditions**
60
Thinning of the cornea with breaks in the Bowman layer are the histologic hallmarks of what condition?
Keratoconus
61
Which 2 conditions are one of the principle indications for corneal transplantation in the US?
- Fuchs endothelial dystrophy
- Pseudophakic bullous keratopathy
62
What are the 2 major clinical manifestations of Fuchs endothelial dystrophy?
1) Stromal edema
2) Bullous keratopathy
63
Fibrous CT deposition between the eptithelium and Bowman layer either by ingrowth from the limbus or perhaps through fibrous metaplasia of the corneal epithelium is known as?
Degenerative pannus
64
Thickening of the stroma with edema giving a **ground-glass appearance** clinically, with resultant blurred vision is characteristic of the late stages of which eye pathology?
Fuchs endothelial dystrophy
65
Mutations in which gene encoding an extracellula matrix protein may lead to improper folding of this protein and lead to depositions in the cornea
*TGFB1* encoding keratoepithelin
66
When the number of endothelial cells decrease following cataract surgery, this condition is known as?
Pseudophakic bullous keratopathy
67
Lenticular opacities that may be congenital or acquired describes?
Cataract
68
What are the risk factors for cataracts?
- Diabetes
- Galactosemia
- Wilson disease
- Atopic dermatitis
- Drugs (**especially corticosteroids**)
- Radiation or trauma
69
What is nuclear sclerosis?
**Age-related** cataract resulting from **opacification** of the **lens nucleus**
70
Migration of the lens epithelium posterior to the lens equator may result in _________ secondary to enlargement of abnormally positioned lens epithelium.
Posterior subscapular cataract
71
What is hypermature or *morgagnian cataract?*
Lens cortex may liquefy almost entirely
72
What is phacolysis and how may it contribute to development of glaucoma?
- **High MW proteins** from liquefied lens cortex *(****morgagnian cataract**)* that leak through lens capsule, potentially clogging the trabecular meshwork and increasing intraocular pressure = **phacolytic glaucoma**
- Example of **secondary open-angle glaucoma**
73
In which type of glaucoma does the peripheral zone of the iris adhere to the trabecular meshwork and physically impede the egress of aqueous humor from the eye?
Angle-closure glaucoma
74
Mutations in what genes have been associated with the development of open-angle glaucoma?
Which population is each gene associated with?
- ***MYOC*** associated w/ juvenile and adult primary open-angle glaucoma
- ***OPTN*** associated w/ some cases of adult open-angle glaucoma
75
What is the most common form of secondary open-angle glaucoma and is associated with polymorphisms in what gene?
- **Pseudoexfoliation glaucoma** = deposition of **fibrillary** material throughout **anterior segment**
- Single nucleotide polymorphism in the lysl oxidase like 1 (**LOX1**) gene
76
What is ghost cell glaucoma?
Senescent red cells **after trauma** clogging up the trabecular meshwork in the presence of an open angle
77
What is episcleral venous pressure and what may it lead to?
- **Elevations** in the pressure **on the surface** of the eye in the presence of an **open angle**
- Contributes to **secondary open-angle glaucoma**
78
What are some of the contributing factors of secondary angle-closure glaucoma?
- **Chronic retinal ischemia** upregulating **VEGF** --\> thin, **fibrovascular membranes** over surface of eye
- Contraction of **myofibroblasts** in these membranes --\> occlusion of trabecular meshwork = **neovascular glaucoma**
- **Retinoblastomas** may also induce iris neovascularization and glaucoma
79
Prolonged use of which drug is a risk factor for glaucoma?
Corticosteroids
80
Primary angle-closure glaucoma typically develops in eyes with shallow anterior chambers, and is often found in individuals with \_\_\_\_\_\_\_.
Hyperopia
81
Endophthalmitis is inflammation where?
Within the interior of the eye and involving the vitreous humor
82
Inflammation within the eye that involves the retina, choroid, and sclera and extends into the orbit is known as?
Panophthalmitis
83
Adhesions between the iris and the trabecular meshwork of the cornea are called?
Can lead to?
- Anterior synechiae
- Elevation in intraocular pressure --\> optic nerve damage
84
Which organism may cause Uveitis?
*Pneumocystis carnii*
85
Granulomatous uveitis is a common complication of \_\_\_\_\_\_\_\_\_\_.
Sarcoidosis
86
When **sarcoidosis** produces **granulomas** in the **retina** giving rise to perivascular inflammation, it produces what well-known opthalmoscopic sign?
Candle-wax drippings
87
Patients with AIDS are at risk of developing eye infections by which organisms?
- CMV retinitis and uveal infection
- *Pneumocystitis* or mycobacterial choroiditis
88
Which condition is characterized by bilateral granulomatous inflammation typically affecting all components of the uvea: a panuveitis?
How is this type of uveitis classified?
Sympathetic opthalmia = **non-infectious uveitis**
89
How may a penetrating injury to the eye lead to Sympathetic opthalmia and potentially blindness?
- Retinal antigens sequestered from immune system may gain access to lymphatics in the conjunctiva
- Sets up **delayed hypersensitivity reaction**, affecting not only the injured eye, but also the contralateral eye
- May develop anywhere from **2 weeks** to **many** **years** following an injury
90
What is the characteristic morphology and cell types found in Sympathetic Opthalmia?
- Diffuse granulomatous inflammation of the uvea (choroid, ciliary body, and iris)
- **Eosinophils** may be present
91
Which unusual feature is commonly seen with Uveal Melanomas and what is this process called?
- **Looping slit-like spaces** lined by **laminin** that surround packets of tumor cells
- These spaces are not BV's, but connect to BV's and serve as **extravascular conduits** for the transport of blood and plasma
- Unusual growth pattern promoted by tumor cells and known as **vasculogenic mimicry**
92
Uveal melanomas containing which cell type and which size characteristic have a worse prognosis?
- Those containing **epitheliod cells** rather than exclusively spindle cells
- The **lateral extent** of the tumor rather than depth is related to a worse outcome
93
What is the prognosis for Uveal melanomas?
- Usually are hidden from sight and have likely been present for some times, so the prognosis is **worse** than cutaneous melanomas
- 80% 5 year survival rate, 40% at 10 years
94
Which layer of the retina due exudates tend to accumulate in?
**Outerplexiform layer**, especially in the **macula**
95
Retinal detachment is defined as the detachment of the retina from what?
**Retina** from the **retinal pigment epithelium (RPE)**
96
Rhegmatogenous retinal detachment is associated with what kind of defect?
Full-thickness
97
Non-rhegmatogenous retinal detachment are associated with conditions?
- Choroidal tumors
- Malignant HTN
98
Malignant HTN may lead to focal infarcts of the choroid which can be seen clinically as?
Elschnig spots
99
The observation of "cotton-wool spots" during an opthalmoscopic observation suggests?
- **INFARCTION** of the **n****erve fiber layer**of the**retina**
- Presence of **cytoid bodies** (accumulaton of mitochondria) populating the **nerve fiber layer**
100
Retinal nerve fiber layer infarcts may develop in association with what other disease?
AIDS
101
Thickening of which structure is a reliable histologic marker of diabtes mellitus in the eye?
**Basement membrane** of the epithelium of the **pars plicata** of the **ciliary body**
102
What are the characteristic changes that occutr with non-proliferative diabetic retinopathy?
- Basement membrane of retinal blood vessels **thickens**
- Number of pericytes relative to endothelial cells diminishes
- **Microaneurysms**
- **Macular edema** (common cause of visual loss in these pts)
- Accumulation of **exudates** in **outer plexiform layer**
103
What are the characteristic of proliferative diabetic retinopathy and potential consequences?
- Appearance of **new vessels** on surface of optic head or retina (**neovascularization**)
- Vitreous humor may separate from internal limiting membrane (**posterior vitrous detachment**) causing massive hemorrhage of disrupter neovascular membrane
- Scarring associated with the organization of the retinal neovascular membrane may wrinkle the retina
- Neovascular membrane may develop on iris surface and contraction may lead to **neovascular glaucoma**
104
Nonperfusion of the retina due to microcirculatory changes is associated with the upregulation of?
VEGF and intra-retinal angiogenesis
105
What is Retinopathy of Prematurity (Retrolental Fibroplasia)?
- At term, **temporal (lateral)** aspect of retinal periphery is **incompletely** vascularized; **Medial** aspect is **vascularized**
- **P****remature or low-birth-weight**infants Tx w/**O2**, immature retinal vessesl in the temporal retinal periphery**constrict**--\>**ischemia** of distal retinal tissue--\> up-regulation of VEGF
- Retinal angiogenesis; contraction of resulting peripheral neovascular membrane may "drag" the temporal aspect of retina toward the peripheral zone, **displacing the macula laterally**
- **Retina may detach all together**
106
The non-proliferative form of sickle retinopathy occurs in individuals with what hemoglobin genotypes?
SS or SC genotypes
107
How may retinal vasculitis and irradiation used to treat intraocular tumors lead to retinal detachment?
Damage to retinal vessels --\> Retinal ischemia --\> Retinal angiogenesis --\> Complications leading to hemorrhage and traction, and potentially detachement
108
What is the final common pathway in both the nonproliferative and proliferative forms of Sickle Retinopathy?
Vascular occlusion
109
What are Hollenhorst plaques?
Fragments of atherosclerotic plaques lodged in retinal circulation
110
Total occlusion of a branch of the retinal artery produces a segmental infarct of the retina, what will be seen when looking at the fundus with an opthalmoscope?
Fundus appears **white** instead of red/orange
111
Total occlusion of the central retinal artery produces a _______ infarct of the retina
Diffuse
112
What characteristic look will the retina and fovea have upon examination following a diffuse infarct of the retina caused by total occlusion of the central retinal artery?
- Retina will appears white/opaque
- Fovea will look **even more red** in contrast to surrounding opacity -- **cherry red spot**
113
What type of Age-Related Macular Degeneration (AMD) is characterized by deposits in the Bruch membrane (drusen) and geographic atrophy of the RPE?
Atrophic or "dry" AMD
114
What occurs in Neovascular or "wet" AMD?
- Characterized by **choroidal neovascularization**
- Vessles that originate from choriocapillaries and **penetrate THROUGH the Bruch membrane** beneath the RPE
- May even go through the RPE to become situated directly beneath the retina
115
What is the current treatment for neovascular AMD?
Injection of VEGF antagonists into the vitreous of the affected eye
116
The vessels of the neovascular membrane associated with "wet" AMD may occasionally leak and create what problems?
- May be a source of hemorrhage --\> **diffuse vitreous hemorrhage**
- Localized suffusion of blood that may be mistaken for an intraocular neoplasm
117
Which gene is associated with the pathogenesis of AMD?
Suggesting that AMD may stem from excess activity of what?
- CFH (complement factor H)
- Excess activity of complement
118
What risk factor associated with the risk-associated genotype for AMD (CFH) have a 144-fold increased risk for developing the neovascular form of AMD?
Those who have smoked at least 10-pack years
119
What is Retinitis pigmentosa and how is it acquired?
- **Hereditary retinal degeneration**
- Can be autosomal recessive, X-linked, or autosomal dominant
\*AD forms appear later in life
120
Retinitis pigmentosa may be a part of which syndromes?
- Bardet-Biedl syndrome
- Usher syndrome
- Refsum disease
121
What occurs to the rods and cones in Retinitis Pigmentosa?
Are both lost to **apoptosis** w/ rods leading to night blindness and cones leading to center field blindess
122
Retinal atrophy associated with Retinitis Pigmentosa is accompanied by what and is seen how clinically?
- Constriction of retinal vessels and **optic nerve head atrophy** ("**waxy pallor"** **of the optic disc**)
- Accumulation of retinal pigment around blood vessels
123
What pathogens associated with IV drug abuse and AIDS may disseminate to the retina resulting in retinal abscesses and visual morbidity?
- **IV drug abuse** ---\> *Candida*
- **AIDS** ---\> CMV
124
What's the difference between familial and sporadic retinoblastoma?
- **Familial**: germline mutation in **one RB allele**
- **Sporadic**: two separate sporadic mutations occur in RB allele
125
Which chromosome is the RB gene found on?
13
126
Retinoblastomas arising in the context of a germline mutation are often \_\_\_\_\_\_\_\_.
Bilateral
127
Retinoblastoma tends to metastasize to what sites?
- Brain
- Bone marrow
- Skull, distal bones, and spinal cord
128
What is the most common route of escape for metastasis by Retinoblastoma and how does this affect prognosis?
- Via **optic nerve**
- Poor prognosis
129
Appearance of retinoblastoma in one eye and retinocytoma in the other eye is characteristic of _____ retinblastoma
Heritable
130
When cells of a retinoblastoma shed into the anterior chamber, aggregate and form nodules on the iris or settle inferiorly, this is known as?
Pseudohypopyon
131
What are the characteristic histologic features of a retinoblastoma?
- Round, oval, or spindle-shaped **hyperchromatic** nuclei w/ scant cytoplasm
## Footnote
**- Flexner-Wintersteiner rosettes**
132
What is a Primary Retinal Lymphoma and which layers are involved?
**- Aggressive** tumor that involves the **two retinal layers** derived from the brain, **neurosensory retina**, and the **RPE**
- Occur in older patients
- Most are **diffuse large B cell lymphomas** commonly spreading to brain via optic nerve
133
What is Anterior Ischemic Optic Neuropathy (AION)?
- Spectrum of injuries to the optic nerve varying from ischemia to infarction
- May produce transient episodes of ischemia with transient vision loss or with total interruption of blood flow can give rise to an optic nerve infarction w/ complete loss of vision
\*Very similar to a **stroke** in the brain!
134
Is acute papilledema from increased ICP associated w/ visual loss?
No
135
What are the morphological differences seen in the optic nerve with a AION and papilledema?
- **AION:** the optic nerve is **swollen** and **pale**
- **Papilledema:** the optic nerve is **swollen** and **hyperemic (increased blood)**
136
Morphological characteristics of glaucomatous optic nerve damage?
- **Diffuse loss of ganglion cells** and thinning of the retinal nerve fiber
- In advanced cases the optic nerve is both **cupped** and **atrophic** (combo **unique** to glaucoma)
137
Leber hereditary optic neuropathy (LHON) results from the inheritance of what mutations?
Mitochondrial gene mutations = Materal inheritance
138
What is unique about the inheritance of Leber Hereditary Optic Neuropathy (LHON)?
What is its typical onset and initial symptoms?
- Maternal inheritance patter due to mitochondrial gene mutations, BUT **males are affect far more commonly (9:1)**
- Age of onset: 10-30 yo
- Begins with **clouding of vision** that may progress to total vision loss
139
What is one of the most important causes of Optic Neuritis?
Often **one of the first manifestations of MS**
140
Which changes are often seen in the end-stage eye: Phthisis Bulbi?
- Exudate or blood btw ciliary body and sclera and the choroid and sclera (**ciliochoroidal effusion**)
- Membrane extending across the eye from one aspect of ciliary body to another
- Chronic retinal detachment
- Optic nerve atrophy
- Presence of intraocular bone (o**sseous metaplasia of the RPE**)
- Thickened sclera
\*Eye may look **square** rather than round
