Chapter 29 part 1

Question 1

Most common cause of irreversible visual loss in US?

Answer 1

AMD (age related macular degeneration)

Question 2

proptosis

Answer 2

eye bulges forward

• enlargement of lacrimal gland from inflammation or neoplasm–eye inferiorly and medially
• 2 primary tumors of optic nerve (glioma, meningioma) – axial proptosis (bulges straight forward)

Question 3

Thyroid Opthalmopathy

Answer 3

• Graves Disease

- Axial proptosis

Question 4

idiopathic orbital inflammation–may affect?

Answer 4

• lacrimal gland (sclerosing dacryoadenitis)
• extraocular muscles (orbital myositis)
• tenon’s capsule, fascial layer that wraps around eye (posterior scleritis)

Question 5

idiopathic orbital inflammation

Answer 5

• chronic inflammation and fibrosis
• inflammatory infiltrate
• vasculitis
• necrosis

Question 6

Most frequently encountered primary neoplasms of the orbit are what in origin?

Answer 6

vascular

• capillary hamangioma (infancy)
• cavernous hemangioma (adults)

Question 7

chalazion

Answer 7

-if drainage system of sebaceous glands is obstructed by chronic inflammation at eyelid margin (blepharitis) or by neoplasm, then lipid may extravasate into surrounding tissue, provoking a granulomatous response–producing a lipogranuloma/chalazion

Question 8

most common malignancy of the eyelid

Answer 8

basal cell carcinoma

Question 9

conjunctiva divided into zones

Answer 9

• palpebral conjunctiva–lines the eyelid
• fornix-where lymphoid population is most noticeable
• bulbar-covers surface of eye

Question 10

what infection produces significant conjunctival scarring?

Answer 10

Chlamydia trachoma’s

-reduction in goblet cells due to scarring-decreased surface mucin-dry eye

Question 11

pinguecula

Answer 11

• next to the limbus (junction of sclera and cornea)
• small, yellowish submucosal elevation
• due to dehydration, a saucer like depression in the corneal tissue may develop–called a delle
• doesn’t invade the cornea like the pterygium

Question 12

ptyergium

Answer 12

• next to limbus
• submucosal growth of fibrovascular CT that migrates into the cornea
• most are benign

Question 13

squamous neoplasms and melanocytic neoplasms tend to develop where?

Answer 13

at limbus

Question 14

conjunctival squamous cell carcinoma preceded by?

Answer 14

-intraepithelial neoplastic changes

Question 15

squamous neoplasms and melanocytic neoplasms tend to develop where?

Answer 15

at limbus

Question 16

conjunctival squamous cell carcinoma–preceded by?

Answer 16

-intraepith neoplastic changes

Question 17

squamous papillomas and conjunctival inraepit neoplasia–associated with

Answer 17

HPV16 and 18

Question 18

conjunctival nevi

Answer 18

• pigmented lesions–represent melanomas or melanoma precursors
• in late childhood–can acquire an inflammatory component–inflammed juvenile nevus

Question 19

conjunctival melanomas affect who? develops by?

Answer 19

• unilateral neoplasms
• affects fair-complexioned patients in middle age
• develop through a phase of intraepithelial growth-primary acquired melanosis with atypia

Question 20

sclera- consists?

Answer 20

• collagen

- few blood vessels and fibroblasts (wounds/surgical incisions heal poorly)

Question 21

immune complexes depositions in sclera produce what?

Answer 21

• necrotizing scleritis

- seen in rheumatoid arthritis

Question 22

sclera may appear blue in what conditions?

Answer 22

• become thin following scleritis; the normally brown color of the urea may appear blue b/c of optical Tyndall effect
• sclera thinned in eyes with high intraocular Pressure
• osteogenesis imperfecta
• heavily pigmented congenital nevus of underlying urea- congenital melanosis oculi

Question 23

major refractive surface of the eye

Answer 23

-cornea and its tear film

Question 24

myopia

Answer 24

eye is too long for its refractive power

Question 25

hyperopia

Answer 25

-eye that is too short

Question 26

bowman layer

Answer 26

-barrier against the penetration of malignant cells from the pith into underlying stroma

Question 27

layers of cornea

Answer 27

-endothelium -descement's membrane -stroma bowman's layer epithelium (in to out)

Question 28

corneal stroma lacks?

Answer 28

BVs and lymphatics--high rate of success of corneal transplantation!!

Question 29

corneal vascularization due to?

Answer 29

-chronic corneal edema, inflammation, scarring

Question 30

keratitis

Answer 30

inflammation of the cornea - dissolution of corneal storm--caused by action of collegenases in corneal epithelium and stroll fibroblasts - exudate and cells leak from iris and ciliary body vessels into anterior chamber--hypophon (visible by penlight) - caused by bacterial, fungal, viral infections--cause corneal ulceration

Question 31

corneal degenerations

Answer 31

unilateral or bilateral | -typically non familial

Question 32

corneal dystrophies

Answer 32

bilateral and hereditary affect selective corneal layers Reis-Buckler dystrophy--bowmans layer -posterior polymorphous dystrophy--affects endothelium

Question 33

2 types of corneal degeneration

Answer 33

- calcified band keratopathy | - actinic band keratopathy

Question 34

calcified band keratopathy

Answer 34

-deposition of calcium in bowman layer

Question 35

actinic band keratopathy

Answer 35

in patients with chronic exposure to UV light - solar elastosis--corneal collagen in interpalpebral fissure - sun damaged collagen of cornea--yellow hue--"oil droplet keratopathy"

Question 36

keratoconus--what is it?

Answer 36

- progressive thinning and ectasia of cornea w/o inflammation/vascularization - bilateral typically - thinning causes a cornea that is conical (not spherical) - irregular astigmatism--diff to correct with glasses - rigid contact lenses

Question 37

histologic hallmarks of keratoconus

Answer 37

- thinning of cornea and breaks in bowman layer - in some patients--descement membrane may rupture--allowing aqueous humor in the anterior chamber to go to corneal storm--corneal hydrous! - vision worsens suddenly

Question 38

Fuchs Endothelial Dystrophy--what is it?

Answer 38

- loss of nedo cells, resulting in edema, thickening of the storm - 1 of the principal indications for corneal transplantation

Question 39

Fuchs Endothelial dystrophy--clinincal--early, later

Answer 39

- early--endothelial cells produce drop like deposits of abnormal basement membrane material (guttata) - later--decrease in endo cells--risidual cells are incapable of maintaining stromal dehydration/deturgescence - stroma--edema, thickens - chronic edema--causes vascularization of storm - epith--hydropic change--detachment of epithelium from Bowman layer

Question 40

stromal dystrophies

Answer 40

- stromal deposits generate discrete opacities in the cornea that can compromise vision - painful epithelial erosions - scarring next to Bowman layer--may cause irregular corneal surface