Eye Disorders

Question 1

mutations in various genes cause damage to the RPE which leads to reduced ability of the RPE to remove shed rod and cone outer segments causing loss of rods and eventual loss of cones

attributed to over 100 mutations
Autosomal dominant, autosomal recessive, or X-linked
Incidence 1/4000

Answer 1

Retinitis pigmentosum (RP)

Question 2

Neural retina detaches from the RPE cells and the rods and cones begin to starve

Patients suddenly see a lot of floaters and can see flashes of light or what seems like a veil interfering with their vision

If not repositioned quickly, the rods and cones die and fibroblast like cells grow over the RPE
Lasers are used to reattach the retina

Answer 2

Retinal detachment

Question 3

most frequent cause of blindness in people over 65

yellow pigment (drusen) accumulates in and around the macula and interferes with vision

no treatment, disease progresses from dry form (non-vascular) to wet form (vascular)

most likely autoimmune and made worse by smoking, hypertension, and obesity

Answer 3

age related macular degeneration (AMD)

Question 4

25% of 60 year olds and 65% of 80 year olds are affected

vitreous liquefies in the center of the eye and eventually flows towards the back of the eye and the posterior wall of the vitreous pulls away from the retina

puts the retina at risk of detachment

Weiss’ ring is the name given to the residue of the vitreous that floats in the posterior chamber

Answer 4

posterior vitreous detachment (PVD)

Question 5

caused by blockage of aqueous outflow via Schlemm’s Canal

results in elevated intraocular pressure and loss of visual function due to loss of rods adn cones within specific visual fields

Answer 5

Glaucoma

Question 6

corneal cloudiness and blindness due to mutations in genes that mediate corneal homeostasis

Answer 6

Corneal Dystrophies

Question 7

accumulation of damaged proteins in the lens is followed by denaturation of proteins and loss of lens clarity

corrected surgically, lens proteins are removed and an artificial intraocular lens is implanted within the lens capsule

Answer 7

Cataracts

Question 8

defects in either the volume of tears produced or in the composition of the tears produced

Allows corneal epithelial denudation to occur which then allows bacteria to adhere and infections to occur

Scarring from infections can interfere with vision

more common in women and incidence increases after menopause

Answer 8

Dry Eye

Question 9

loss of visual acuity
dyschromatopsia (loss of color vision, typical of optic nerve deficit)
visual field defect
deficit in contrast sensitivity
relative afferent pupillary defect (RAPD)
normal or abnormal optic disc
abnormal visual evoked potential (VEP)

Answer 9

consequences of optic nerve neuropathy

Question 10

optic disc edema caused by increased intracranial pressure

results from accumulation of axoplasmic elements in the optic nerve from an increase in ICP

mechanical distortion and vascular factors contribute because of the increased ICP at lamina cribrosa

clinical features:
elevation of optic disc, blurring of optic margins 
obscuration of retinal vessels
hyperemia and dilation of the capillary net
retinal venous dilation
peripapillary hemorrhages
retinal choroidal folds 
macular edema

Answer 10

Papilledema

Question 11

hyperemic ON, dilation of capillary net, telangiectasias of surface and radial peripapillary vessels, flame heme, peripapillary NFL, grayish white margins, obscure retinal vessels, disc edge, absence of venous pulsations (VP)

grade I: C-shaped halo with a temporal gap
grade II: halo becomes circumferential
grade III: loss of major vessels as the leave the disc
grade IV: loss of major vessels on the disc
grade V: partial or total obscuration of all vessels on the disc

Answer 11

acute papilledema

Question 12

gliosis of peripapillary NFL, grayish opacification, more membranous, vascular sheathing

optociliary shunt vessels from preexisting venous channels on disc surface that dilate in response to chronic retinal vein obstruction from elevated ICP

refractile bodies of the disc – chronic lipid exudation, smaller than drusen and noncalcified

Answer 12

chronic papilledema

Question 13

optic disc edema in the absence of increased ICP

blurred disc margins located deep to retina blood vessels (vessels are clear and visible as they cross disc margins)

causes:
optic nerve drusen
crowded disc
astrocyte hamartoma
optic disc hypoplasia
optic disc coloboma

Answer 13

pseudopapilledema

Question 14

headache, nausea, vomiting
more common in females in third decade
associated with obesity, pregnancy, vitamin A excess, tetracyclines (think acne treatment), nalidixic acid, cyclosporine, OCP use, corticosteroids, superior venous thrombosis
transient visual obscurations (loss of vision for a few seconds on certain movements)
diplopia due to CN VI palsy
increased blind spot
pulsatile tinnitus
dizziness
increased opening pressure (>200mmHg) on lumbar puncture and normal CSF composition

no other causes of ICP can be identified (mass, vascular lesion, structural lesion) – R/O with MRI

there are signs of increased ICP but papilledema is not necessary for diagnosis
there is an absence of neurological signs except for CN VI palsy

Neuroimaging: Empty sella 25%,
Flattening of globe, Enlarged optic nerves, Protrusion/enhancement of optic nerve head, Increased tortuosity of optic nerve

Mechanism of increased ICP is unknown
Absorption of CSF across arachnoid granulation into dural venous sinuses is impaired
Associated with cerebral venous obstruction, dural AV malformation, systemic vasculitis (decreased outflow, increased ICP)

Magnetic resonance venogram (MRV) is used to r/o thrombosis of cerebral venous sinuses in atypical presentations (male, nonobese, suspected coagulopathy)

Follow-up work-up with visual acuity, color, visual field testing

Management:
Acetazolamide (Diamox) – risk of tingling in extremities and kidney stones
Furosemide if intolerant to acetazolamide
Corticosteroids (controversial)
Weight loss

With intractable headaches and progressive visual fields deficits on max meds – surgical interventions
Optic nerve sheath fenestration with progressive vision loss
CSF diversion procedure with headaches, CN VI palsy, papilledema
Lumboperitoneal or ventriculoperitoneal shunt
Morbid obesity: gastric bypass

Prognosis:
Better prognosis with better visual acuity
Gradual improvement with treatment but not necessarily recovery
Significant vision loss at presentation suggests higher risk
Worse prognosis: female, black race, HTN, anemia, younger age, severe obesity, severe papilledema

Answer 14

idiopathic intracranial hypertension (IIH)

Question 15

opacity of the crystalline lens

age related or secondary to an insult – inflammation, trauma, drugs

multiple types: cortical, nuclear sclerosis, posterior subcapsular, white mature, traumatic, congenital

leading cause of reversible blindness worldwide

decreased vision, glare, inability to perform activities of daily living, trouble with small print reading

treatment:
glasses to correct refractive error
surgery - now use extracapsular technique in which the capsule is opened (capsulorhexis), the lens is broken down and aspirated (phacoemulsification), and an artificial lens is inserted
complications are uncommon but sight threatening
no medical prevention available

Answer 15

Catract

Question 16

elevated intraocular pressure due to functional obstruction of trabecular meshwork

optic nerve cupping (loss of retinal NFL leads to increase in cup in center of nerve)

visual field defects (usually arcs in peripheral visual field, advances without treatment)

increases with age and is asymptomatic

reduce intraocular pressure with topical eye drops, laser treatment to trabecular meshwork, or surgery

Answer 16

primary open angle glaucoma

Question 17

common – associated with ASA, warfarin, straining (increased intrathoracic pressure)
especially common in the elderly

appears serious but is not

small about of blood is layered between the conjunctive and sclera

resolves with time, no treatment needed

Answer 17

subconjunctival hemorrhage

Question 18

most common cause of pink eye

redness, watery discharge, foreign body sensation, blurry vision

adenovirus, HSV, MMR

follicles, pre-auricular LAD, conjunctival membranes, corneal sub-epithelial infiltrates

counsel patient, will get worse over 4-7 days and lasts 2-3 weeks; highly contagious, hand washing is important

Answer 18

viral conjunctivitis

Question 19

less common cause of pink eye

purulent discharge, redness, discomfort
papillae, chemosis

staph, pneumococcus, Moraxella, Haemophilus, gonococci (hyperacute), chlamydia

culture if not responding to empiric treatment, severe, or recurrent

treat with polytrim or fluoroquinolone drops
H. flu – systemic antibiotics
Neisseria – IM/IV antibiotics

Answer 19

bacterial conjunctivitis

Question 20

Yellow flat or raised lesion in palpebral conjunctiva that does not involve the cornea

nasal or temporal actinic changes
redness, irritation

elastoid degeneration of conjunctiva from UV light exposure

treat with lubrication, anti-inflammatories, no surgical intervention required

Answer 20

Pingueculum

Question 21

wing shaped fibrovascular growth extending to the cornea resulting from UV light exposure

can grow over the visual axis or cause significant astigmatism

decreased vision, redness, irritation

treat with lubrication, topical NSAIDs, topical steroids, surgery (excision with conjunctival autograft or amniotic membrane)

Answer 21

Pterygium

Question 22

inflammation of the episclera

causes: idiopathic, infectious, rosacea, thyroid dysfunction

redness, discomfort (moderate), no discharge

sectoral or diffuse redness
phenylephrine test shows blanching
cotton tipped applicator test shows mobile redness

if recurrent: ANA, RF, ESR, uric acid, RPR, FT-ABS, ANCA work-up

treatment: time, oral NSAIDs, topical steroids

Answer 22

episcleritis

Question 23

inflammation of the sclera

severe pain (tender to touch), acute red eye, recurrent symptoms

inflammation of scleral vessels – no blanching with phenylephrine or movement with cotton tipped applicator test

scleral edema or thinning

subtypes: diffuse anterior, nodular anterior, necrotizing with inflammation, necrotizing without inflammation, posterior
etiology: RA, ANCA-associated, PAN, reactive arthritis, IBD, herpes zoster, syphilis, TB, gout
treatment: systemic steroids or immunosuppressants

Answer 23

scleritis

Question 24

leukoplakic or grey-white gelatinous lesion, usually at the limbus

middle age – elderly

unilateral, unifocal

dysplasia, carcinoma in situ, can become invasive

treatment: complete excision with cryotherapy at the margins

Answer 24

conjunctival intraepithelial neoplasm (CIN)

Question 25

superficial epithelial defect usually secondary to trauma

extremely painful, redness, tearing, decreased vision

topical antibiotics, cycloplegia, patching, bandage contact lens
no steroids or topical anesthetics

usually heals within 48-72 hours, self-limiting but secondary infection is possible

Answer 25

corneal abrasion

Question 26

infection of the cornea leading to infiltrative necrosis

bacterial, fungal, viral, protozoal (acanthamoeba)

risk factors: contact lens wear, trauma, loose suture

severe pain, redness, photophobia, decreased vision

white opacity (infiltrate), epithelial defect, stromal edema, anterior chamber reaction, hyopyon

scraping and culture of focal opacity

treatment depends on etiology – medical intervention or surgical intervention (corneal transplantation if perforation or uncontrolled infection spreads to limbus or sclera)

Answer 26

infectious keratitis (corneal ulcer)

Question 27

most common infectious cause of corneal blindness in the US (type 1 more than type 2)

primary or recurrent (latent in trigeminal ganglion)

seen in younger adults

redness, pain, irritation, decreased vision, vesicles

types: dendritic epithelial keratitis, stromal keratitis, endotheliitis, keratouveitis

treat with oral antivirals +/- topical antivirals, topical steroids

Answer 27

herpes simplex virus keratitis

Question 28

ocular involvement affects ophthalmic nerve (V1)

immunosuppressed, elderly, HIV/AIDS

keratitis, uveitis, scleritis, retinitis, vasculitis, optic neuritis

dermatomal pain, skin rash, decreased vision, photophobia, redness

treat with oral antivirals 7-10 days, topical steroids with slow taper

Answer 28

herpes zoster ophthalmicus

Question 29

inflammation of the uveal tract

types: anterior, intermediate, posterior, panuveitis, acute/chronic

idiopathic, autoimmune diseases, syphilis, TB, lyme

pain, redness, photophobia, decreased vision, floaters

ciliary flush, AC cells/flare, KPs, hyopyon, posterior synechea, vitritis, retinal vasculitis, macular edema

treatment: topical steroids, systemic steroids, immunosuppressants; if infectious treat agent

Answer 29

iridocyclitis

Question 30

asymptomatic or decreased vision

arteriolar narrowing, AV nicking, cotton wool spots, flame shaped hemorrhages, arterial macroaneurysms, branch retinal vein occlusion, optic nerve edema

check BP, refer to internist if greater than 200/110

Answer 30

hypertensive retinopathy

Question 31

Acute unilateral painless vision loss (CF to light perception)

Types: central, branch retinal

Whitening of the retina, cherry red spot, afferent pupillary defect, retinal emboli

Etiology: embolus, thrombosis, giant cell arteritis, collagen vascular disease

Work up: CRP, check BP, HBA1c, PT/PTT, ANA, RF, FTABS, antiphospholipid antibodies

Treat with ocular massage, anterior chamber paracentesis, reduction of intraocular pressure, hyperventilation

Answer 31

retinal artery occlusion

Question 32

painless loss of vision, usually unilateral

diffuse retinal hemorrhage, cotton wool spots, dilated tortuous retinal veins, macular edema, neovascularization

HTN, atherosclerotic vasculature, optic disc edema, glaucoma, hypercoagulable states, vasculitis

Treat macular edema with intravitreal antiVEGF agents
Treat neovascularization with PRP

Answer 32

retinal vein occlusion

Question 33

Micro angiopathy with prolonged hyperglycemia

Types: non-proliferative, proliferative, diabetic macular edema

Decreased vision

Microaneurysms, hemorrhages, hard exudates, neovascularization

Treat with laser photocoagulation, antiVEGF injections

Answer 33

diabetic retinopathy

Question 34

Leading cause of visual loss in adults over 65

Types: non-exudative, exudative

Painless gradual vision loss

Drusen = yellowish subretinal deposits
Geographic atrophy, macular edema

Treat with antiVEGF agents and photodynamic therapy

Answer 34

macular degeneration

Question 35

Ocular emergency

Acute rise in intraocular pressure due to pupillary block
physical block by the iris

Pain, blurred vision, colored haloes, frontal headache, nausea, vomiting

Closed angle gonioscopy, corneal edema, fixed mid dilated pupil, conjunctival injection, shallow to flat anterior chamber

Work-up: slit lamp exam, measure IOP, gonioscopy (examine angles), fundoscopy

Treat with beta blockers, alpha 2 agonists, carbonic anhydrase inhibitors, laser peripheral iridotomy

Answer 35

acute angle closure glaucoma

Question 36

Ocular emergency
Purulent inflammation of the inner coat of the eye with progressive vitritis

Post-operative, post-traumatic, endogenous, acute/chronic

Sudden onset decreased vision, eye pain, photophobia, redness

Eyelid edema, conjunctival injection, corneal edema, chemosis, hypopyon, firbin, severe anterior chamber reaction, virtitis, decreased red reflex

Look for wound leak, exposed suture, predisposing factor
Bscan (ultrasound) if posterior segment is not visible
Vitreous tap for cultures

Staph, step, gram neg, fungus, anaerobes

Treat with fortified antibiotics, topical steroids
If vision is more than light perception, vitreous tap or injection of antibiotics
If vision is less than or only light perception, vitrectomy and injection of antibiotics

Answer 36

endophthalmitis

Question 37

Ocular emergency
Infection of the eyelid/periorbital tissues, anterior to orbital septum

Etiology: periorbital trauma of skin infection (impetigo) or ethmoid sinus disease

Limited to superficial periorbital tissues (not the conjunctiva), less serious

Eyelid swelling, pain, erythema, tenderness

Tense edema, warmth, tenderness, no proptosis, vision/mobility normal, no pupillary defects, no optic nerve involvement, no ocular involvement

Complete ocular exam, facial sensation, CBC, blood cultures, orbit and sinus CT

Systemic antibiotics (oral or IV depending on severity)

Answer 37

preseptal cellulitis

Question 38

Ocular emergency
Infection within the orbital cavity

From preseptal cellulitis, sinus infection, dental infection, trauma, orbital surgery

Eye pain, redness, double vision, blurry vision, eyelid swelling, fever

Eyelid edema, proptosis, chemosis, restriction of ocular motility, optic nerve compression (APD), decreased vision, corneal sensation, optic disc edema

Risk for blindness due to compartment syndrome (check pupils)

Complete ocular exam, blood work, CT

In adults – staph, strep, bacteroides; in children – haemophilus

Admit for broad spectrum IV antibiotics, canthotomy to relieve compression, reimaging, drainage of abscess if present

Complications: subperiosteal or orbital abscess

Answer 38

orbital cellulitis