Eye Physiology & Pathology Flashcards
What forms the socket of the eyeball?
1) Tenon capsule (fascial sheath)
Presence of necrotic collagen with vasculitis within the orbit?
1) Wegener granulomatosis
What is the most frequently encountered primary tumor of the orbit?
1) Tumor of vascular orgin
What is the most common malignancy of the eyelid?
Basal cell carcinoma
Where is lymphoid tissue in the conjunctiva normally found?
1) Normally found in the conjunctiva of the fornix
Yellow submucosal elevation that is located near the limbus; does not invade the cornea; may form dellen
Pinguecula
What is a dellen?
1) saucer like depression in the corneal tissue
2) May be caused by Pinguecula
Submucosal elevation of the conjunctiva that is formed by fibrovascular connective tissue that migrates onto the cornea
Pterygium
Site of copper deposition in Wilson’s disease?
1) Descemet membrane
What is the hallmark finding of chronic Herpes simplex virus infection in the cornea?
1) Granulomatous reaction in the descement membrane
Calcium in the bowman layer
Calcific band keratopathy
What are the layers of the cornea?
1) Epithelial layer and basement membrane
2) Bowmen layer (acellular)
3) Corneal stroma
4) Descemet membrane
5) Corneal endothelium
What is the site of copper deposition in Wilson’s disease? What is the name of these lesions?
1) Descemet membrane
2) Kayser-Fleischer rings
What is the cause of Actinic band keratopathy? What is the pathologic pathway of this disease?
1) Caused by exposure of to high levels of UV light
2) Extensive elastosis develops in the superficial layers of the cornea
Progressive thinning and ectasia of the cornea without evidence of inflammation or vascularization; cornea develops a cone shape, causes astigmatisms; occcurs bilaterally
Keratoconus
What is keratoconus associated with?
1) Down syndrome and Marfan syndrome
2) Occurs bilaterally
What occurs when the thinning of the cornea occurs in Keratoconus?
1) Cone shaped cornea
2) Breaks in the Bowman layer
3) Descemet membrane rupture
What is associated with Descemet membrane rupture
1) Corneal hydrops
Extension of aqeuous humor from the anterior chamber into the gain access to the corneal stroma due to Descemet membrane rupture
Corneal hydrops
Drop-like deposits of abnormal basement membrane material produced by endothelial cells early in the course of Fuchs Endothelail dystrophy
Guttata
What are the two manifestations observed in Fuchs Endothelial dystrophy?
1) Stromal edema - stroma has a ground/glass appearance
2) Bullous keratopathy
Where is aqeous humor of the posterior and anterior chamber produced?
Pars plicata of the ciliary body
How do you differentiate between a Chalazion and Sebaceous carcinoma?
1) Sebaceous carcinoma tends to spread to the parotid and submandibular glands
2) Presence of vacuolization the cytoplasm
3) Reccurence of a Chalazion indicates a sebaceous carcinoma
Granulomatous response due to the blockage of sebaceous glands in the eyelid that results in producing a lipogranuloma
Chalazion
What are the most important factors for prognosis
1) Cell type
2) Diameter
What cell type has a promising prognostic factor of Uveal melanoma? Worsening prognosis?
1) Spindle cell type
2) Epithelioid cell type
3) Proliferative index
Cause of primary open angled glaucoma?
1) Mutation of MYOC gene
Where does a Sebacous carcinoma of the eyelid normally spread to first?
1) Parotid and submandibular nodes
Autoimmune disorder characterized by lymphocytic invasion of the parotid and submandibular glands
Sjogren syndrome
What is the classic triad for Sjogren syndrome?
1) Xerophthalmia -dry eyes
2) Xerostomia- dry mouth
3) Arthritis
Inflammation of the interal coats of the eye; inflammation of the viterous cavity
Endophthalmitis
Inflammation of all layers of the eye
Panophthalmitis
What does the uvea consist of?
1) Iris
2) Choroid
3) Ciliary body
How do uveal melanomas spread? Where do they spread?
1) Hematogenously
2) Liver
Separation of the neurosensory retina from the retinal pigment epithelium
Retinal detachment
What is the difference between Rhegmatogenous and non-rhegmatogenous retinal detachment?
Rhegmatogenous is caused by a retinal tear
What causes the “cotton wool spots” on ophthalmic evaluation?
1) Collection of cytoid bodies
What are cytoid bodies?
1) accumulation of mitochondria at the swollen ends of damaged axons in the nerve fiber layer
2) Form due to occlusions of arteroiles
What does thickening of the ciliary body basement membrane indicate?
Chronic diabetes mellitus
Describe the layers of the retina.
1) Internal limiting membrane
2) Nerve fiber layer
3) Ganglion cell layer
4) Inner plexiform layer
5) Inner nuclear layer
6) Outer plexiform layer
7) External limiting membrane
8) Rods and cones
9) Retinal Pigment Epithelium
What is the origin of retinoblastoma?
Neuronal
Tumor that consists of both differentiated and undifferentiated components; Flexner Wintersteiner rossettes and collection of small, round cells with hyperchromatic nuclei
Retinoblastoma
Spectrum of injuries to the optic nerve due to vascular causes; may produce episodes of transient loss of vision
Anterior Ischemic Optic Neuropathy (AION)
Diffuse loss of ganglion cells and thinning of retinal nerve fiber layer; may have cupped CNII; elevated intra-ocular pressure
Glaucomatous Optic Neuropathies
Presence of exudate or blood between the ciliary body and sclera; presence of a membrane extending across the eye; chronic retinal detachment; optic nerve atrophy
Phthisis bulbi
Optic nerve cupping
Glaucoma!
Autosomal recessive condition causing deposition of keratan sulfate that results in gray opacities in the cornea
Corneal dystrophy
Eye is too short for refractive power of cornea and lens; light focused behind retina
Hyperopia
Eye too long for refractive power of cornea and lens; light focused in front of retina
Myopia (think: MY that’s long, the focus can’t reach the retina)
Abnormal curvature of cornea resulting in different refractive power at different axes
Astigmatism
Decrease change in focusing during accommodation
Presbyopia
Causes of retinitis
Usually viral; associated with immunosuppression
1) CMV
2) HSV
3) HZV
Causes of cataracts
1) Classic galactosemia
2) Galactokinase deficiency
3) Diabetes
4) Trauma
5) Infection
Deposition of yellowish extracellular material beneath retinal pigment epitheilum
Dry age related macular degeneration
Rapid loss of vision due to bleeding secondary to choroidal neovascularization
Wet Age related Macular degeneration
What provides site for the lower retina (provides superior vision)? Where does it travel?
1) Meyer’s Loop
2) Loops around inferior horn of lateral ventricle
What provides site for the upper retina (provides inferior vision)? Where does it travel?
1) Dorsal optic radiation
2) Takes shortest path through internal capsule
Spherical tau proteins
Picks disease
Hyperphosphorylated tau protein
Alzheimer
alpha synuclein containing inclusions
Lewy bodies
Pt presents with blurry and distorted vision. No Hx of diabetes or hypertension. Opthalmologic examination of the right eye reveals a gray subretinal membrane.
Wet Age related Macular Degeneration
Main cause of wet age related macular degeneration
VEGF
Subretinal drusen deposits or pigment changes with vision loss
Dry Age related Macular degeneration
