3-23 Pathology of the Eye Flashcards
Familiarize yourself with the normal anatomy of the eye.
Yup
More normal eye anatomy.
What is the limbus in regards to the eye?
structure at edge of anterior chamber that represents the fusion of 3 layers:
conjunctiva, episclera, and sclera all fusing onto cornea
What artery can be occluded to cause blindness? What are the causes of occlusion?
1)Retinal artery occlusion (or one of its branches, from ophthalmic artery and/or cavernous int carotid aa)…usually due to
A) atheromatous emboli from ipsilateral internal carotid stenosis;
B) stenosis from HT, diabetes;
C) vasculitis
- infarction of entire artery (or part of)
What is amaurosis fugax?
TIA of retinal artery (or branches of) = “Amaurosis fugax”… “browning out” or “loss of vision” in one eye for about 10 minutes …usually caused by ipsilateral internal carotid stenosis.
What is anterior ischemic optic neuropathy?
2) neuropathy…short posterior ciliary arteries (branches of the ophthalmic artery)…supply anterior optic nerve.…occlusion results in sudden vision loss in one eye (common in patients over 50)…classic onset is upon wakening
- sometimes seen in temporal arteritis
What are the tumors of the peri-ocular regions?
- Basal cell carcinoma
- Squamous cell carcinoma
- Sebaceous cell carcinoma
- Nevi (Benign tumors)
What is the most common eyelid malignancy? What structures does it preferentially affect?
- Most common eyelid malignancy (~ 25 times more common than SCC)
- Lower lid>medial canthus>upper lid>outer canthus
What forms of basal cell carcinoma are present as an eyelid malignancy? What histo and gross forms might it take?
- Nodular, cystic, diffuse
- Islands of basaloid cells with peripheral palisading, stromal desmoplasia, retraction artifact
- Ulceration may or may not occur;
- Pigmentation may occur, simulating a melanoma
Is BCC of the eyelid often metastatic?
•Locally invasive, rarely metastasizes
What’s this?
BCC
What’s this?
BCC
What population is most likely to get SCC on the eyelid? Is it metastatic?
- Elderly fair-skinned individuals
- Potential for local or distant metastasis
What forms, gross & histo, can SCC take?
- Lower lid most common
- Typically shallow ulcer surrounded by a wide, elevated, and indurated border
- Polygonal cells with pink eosinophilic cytoplasm, nuclear atypia, infiltrating cords into dermis, dyskeratotic cells, keratin pearls.
What’s this?
SCC
What’s this?
SCC
What’s this?
SCC
What population is more affected by sebaceous carcinoma of the eye?
•Elderly, more female, > Asians
What can sebaceous carcinoma of the eyelid mimic? What part of the eye does it most often arise from?
- Can mimic chalazion or chronic blepharoconjunctivitis
- 2/3rds in upper lid
What glands can sebaceous carcinoma arise from? What is its appearance histologically?
- Can arise from meibomian, Zeis (lash follicules) or caruncle glands
- Malignant cells with foamy, lipid-laden cytoplasm, necrosis, pagetoid invasion of the skin
What is the mortality of sebaceous carcinoma? What structures are affected by metastasis?
•15% mortality, direct extension and distant metastasis (lung, liver, brain, skull)
What are the tumors of the eye?
- Retinoblastoma
- Conjunctival Melanoma and Squamous Cell Carcinoma
- Uveal Melanoma
What is the frequency of retinoblastoma?
- Most common intraocular tumor of childhood (90% dx before age 3)
- Frequency: 1/14,000 to 1/20,000 live births
- In the US, approximately 250-500 new cases occur/ yr
What is the difference between b/l and sporadic cases of retinoblastoma?
- 30-40% are bilateral…associated with germ line mutations.
- Sporadic cases are associated with somatic mutations.
Eighty five percent of retinoblastomas are sporadic. Fifteen percent are autosomal dominant and are often bilateral and multiple.
What are the SSXs of retinoblastoma? What gene is involved?
•Signs/symptoms
–Leukocoria, strabismus, red,
–painful eye, poor vision
•Retinoblastoma gene Chr 13 (tumor suppressor)
What type of tumor is retinoblastoma? What is it similar to?
Retinoblastoma is a malignant embryonal tumor of the eye similar to medulloblastoma.