Eye Diseases Flashcards
What are the components of a basic eye exam?
Vision, pupils, confrontation visual fields, extra-ocular motility, direct ophthalmoscopy
What region of the retina is tested in visual acuity tests?
Fovea
What is meant by vision results like “20/XX” (ex. 20/20, 20/80)?
It means the patient can read at 20 feet what a “normal” person can see at XX feet
What is fluorescein angiography?
Dye is injected into the arm and photographs are taken of the retina
What is optical coherence tomography?
Non-contact digital optical instrument that generates cross sectional images of the retina
Why is it important to check visual fields in a patient complaining of visual loss who has an otherwise normal eye exam?
Patients can have normal tested vision but have a visual field defect due to a brain lesion
If a patient has abnormal motility and visual loss, what do you need to be concerned about?
Multiple cranial nerve palsies, may need brain/orbit imaging
What should you see on fluroscein angiography if a patient has ophthalmic artery occlusion?
The ophthalmic artery supplies both the central retinal artery and the ciliary arteries, so you would see delay in filling of both circulations
What are the most common causes of “red eye” and what history and findings are important?
Conjunctivitis - discharge from eye, follicles on conjunctiva, recent illness
Uveitis - light sensitivity, progressive symptoms
Corneal ulcer - contact lens wearer
Allergy - itchy and teary eye
Subconjunctival hemorrhage - very red, minimal symptoms
Dry/irritated eye - lack of sleep, dust exposure, burning/sharp pain
Chemical injury
Angle closure glaucoma - check intraocular pressure
What are the symptoms of a cataract?
Changes in refraction, contrast, glare, decreased night vision, overall blurred vision (later symptom)
What are the causes of cataracts?
age, UV exposure, diabetes, uveitis, steroids, trauma, medications/medical conditions
What is the difference between open angle glaucoma and angle closure glaucoma?
Open angle - slowly progressive and generally not symptomatic in mild to moderate disease
Angle closure - acute, accompanied by severe pain, nausea, headaches
What are treatments for glaucoma?
Medically: beta-blockers, alpha-agonists, carbonic anhydrase inhibitors, prostaglandin analogs, systemic carbonic anhydrase inhibitors
Surgery: laser procedures, incisional surgery
How can a ruptured globe be recognized, and how is it managed?
Usually occurs post-trauma - diagnosed with CT scan and siedel test
The globe should not be touched - it should be shielded and ophthamology should be consulted
What conditions require an ophthamology consult?
Acute glaucoma, corneal ulcers, ruptured globes, severe chemical injury, significant flashes/floaters, decreased vision
What is the limbus?
The edge of the cornea - the point where the sclera and conjunctiva began
What is the conjunctiva?
A clear membrane attached to the eyelids and the limbus to prevent foreign objects from accessing the orbit
What is conjunctivitis?
hyperemia (engorgement) of the conjunctival blood vessels
What is episclera?
Outermost layer of the sclera, situated between the sclera and conjunctiva
What is episcleritis?
Benign, often self-limiting inflammation of the episclera
What is scleritis?
inflammation of the sclera that is painful and tender to the touch, can cause vision loss if it affects the retina
What systemic disorders are associated with scleritis?
rheumatoid arthritis, granulomatosis with polyangitis, polyarteritis nodosa, and lupus
What are the five layers of the cornea?
epithelium (outermost), Bowman’s layer, stroma, Descemet’s membrane, endothelium (innermost)
How much of the total refractive power of the human eye is from the cornea?
40 of the 60 total diopters
What is myopia?
near-sightedness
What is hyperopia?
far-sightedness
What is the most common risk factor for corneal ulcers?
history of contact lens wearing
What is the effect of herpes virus in the cornea?
It can infect different layers, herpetic keratitis of the epithelial layer is the most common
What should the initial treatment be for chemical injury to the eye?
Copius high volume and pressure irrigation
What are cataracts?
Opacification of the lens as a result of aging or disease
How are different types of cataracts categorized?
By their location - capsule, nucleus, or cortex of the lens
What type of cataract is typically age related? What are the symptoms?
Nulcear cataract
Symptoms = myopia, decreased contrast sensitivity, yellow tint to vision
Which eye disease is most directly related to a smoking history?
cataracts
What is glaucoma?
A disease of high pressure that causes damage to the optic nerve that causes a loss of peripheral vision first and ultimately total blindness if left untreated
What is the appearance of the optic nerve on fundoscopy in glaucoma?
It has a small central depression (cup) in the optic nerve
What is laser iridotomy?
A surgical procedure where a hole is put in the iris to allow the aqueous humor to flow
What is the seidel test?
A test for anterior chamber leakage from a wound, visualized with fluorescein dye
What are possible vitreous-related conditions?
posterior vitreous detachment (normal part of aging)
vitreo-retinal interface abnormalities
vitreous hemorrhage
What are the symptoms of retinal tear/detachment?
flashing lights, floaters, curtain effect (loss of vision in top of visual field bilaterally)
What is the treatment for retinal tears/detachment?
surgical intervention (scleral buckle, pars plana vitrectomy)
What are the types of diabetic retinopathy?
nonproliferative and proliferative
nonproliferative is an earlier stage, proliferative involves angiogenesis
What features can be seen on fundoscopy of diabetic retinopathy?
microaneurisms, exudates, blot hemorrhages
What is the treatment for diabetic macular edema?
anti-VEGF and focal laser photocoagulation
What are drusen?
Deposits found in dry age related macular degeneration
What is neovascular age related macular degeneration?
A form of age related macular degeneration where there is vascular growth in the sub-RPE and sub-retinal spaces
What are the current treatments for neovascular age related macular degeneration?
anti-VEGF agents, anti-oxidants
What should you consider when a patient presents to you with flashing lights and floaters?
flashing lights = stimulation to retina (pulling or fluid)
floaters = something floating in vitreous (vitreous condensations, blood, wbc)
together these are signs of a retinal detachment
Why should a diabetic patient receive eye exams routinely?
DM can affect the integrity of blood vessels in the eye that result in microaneurysms, hemorrhages, cotton wool spots, and exudates. Neovascularization can occur in advanced retinopathy
Why should patients with macular degeneration be counselled to monitor each eye separately?
Early treatment is important for maintaining good central vision
Suddent distorted vision may mean macular degeneration has become exudative (requires prompt treatment)
What systemic conditions would you consider in a patient with retinal artery occlusion? Retinal vein occlusion?
Artery occlusion: hypertension, diabetes, hypercholesterolemia, embolism, giant cell arteritis (in elderly patients)
Vein occlusion: hypertension, diabetes, hypercholesterolemia, hypercoaguable state
What is the cause of the pie in the sky visual field defect?
Defect of the temporal lobe lesion
What is the effect of occipital lobe defects on vision?
either both on left or both on right side, often quadrantanopia
also often macula sparing
What is the cause of anisocoria that is worse in the dark?
Dilation problem, smaller pupil
can be caused by Horners syndrome
What is the cause of anisocoria that is worse in the light?
Constriction problem
larger pupil - Adies pupil, third nerve palsy
What is anisocoria?
Different sized pupils
What are “imposters” of 6th nerve syndrome?
Duane’s syndrome, thyroid eye disease, convergence spasm, myasthenia
What are common lesions that cause a sixth nerve palsy?
meningiomas, chorodoma, nasopharyngeal cancer
What are some conditions that limit adduction?
Internuclear ophthalmoplegia (brainstem stroke or multiple sclerosis)
partial third nerve palsy
myasthenia gravis
What are the signs/symptoms of fourth nerve palsy?
vertical binocular diplopia
head tilt or turn
inferior oblique overaction
“three step test” diagnosis
What are clinical features of third nerve palsy?
eye “down and out”
binocular diplopia with ptosis
weakness of two or more muscles
anisocoria worse in light
What are the clinical features of optic neuritis? What systemic disease is associated with it?
acute, unilateral vision loss with pain on eye movement
associated with multiple sclerosis
What are the findings of the optic neuritis treatment trial?
contrast sensitivity most often abnormal
fundus findings often normal
MRI findings frequently normal or can have T2 bright lesions
What is the clinical presentation of anterior ischemic optic neuropathy?
older patients with vasculopathic risk factors experiencing sudden vision loss and mild pain that can progress for 2+ weeks
What are the physical exam findings of anterior ischemic optic neuropathy?
- any level of acutiy possible
- dyschromatopsia
- afferent pupil defect
- inferior altitudinal VF
- swollen nerve (pale swelling)
- splinter hemorrhages
What are the eye symptoms of giant cell arteritis? Systemic/other symptoms?
Ocular: visual loss, diplopia, pain, amaurosis fugax (blindness due to lack of blood flow)
Other: occult giant cell temporal arteritis, headache, scalp tenderness, jaw claudication, fever, weight loss, malaise
What is the treatment for giant cell arteritis?
steroids and hydration (IV when vision loss is present) and possibly anticoagulation
What is papilledema?
optic disc swelling due to increased intracranial pressure
What are the ophthalmoscopic features of papilledema?
bilateral disc elevation, obscured disc margins/blood vessels, venous distension/tortuosity, absent spontaneous venous pulsations
What is the clinical presentation of pseudotumor cerebri (idiopathic intracranial htn)?
Often presents with a headache in obese young women, may cause blinding, transient visual obscurations, diplopia
How is idiopathic intracranial htn diagnosed? What are known causes?
Diagnosis of exclusion
Known causes: decreased flow through arachnoid granulations, Addison’s disease, nutritional disorders, metabolic alterations, steroids
What are the treatments for idiopathic intracranial hypertension?
weight loss, diamox, csf shunting procedure or optic nerve sheath fenestration
What is ametropia?
A condition in which light does not focus on the retina
What is myopia?
Light focuses anterior to the retina in an eye that is overpowered
What is hyperopia?
Light focuses posterior to the retina in an eye that is underpowered
What is astigmatism?
Light focuses to different points depending on the axis of incident light
What is presbyopia?
Reduced accomodation (occurs with advanced age)
What is amblyopia?
blurred vision due to failure of the visual pathway to fully develop - occurs piror to age 9 either because a clear image is not presented to the retina or the eyes are properly aligned, may be reversible if diagnosed early
What is the synkinetic reflex?
convergence of the eyes and miosis linked to accomodation
What is the most powerful refractive element of the eye?
Cornea
Nuclear cataract (increases/decreases) lens power by (increasing/decreasing) the index of refraction?
Nuclear cataract increases lens power by increasing the index of refraction?
What axial length is associated with myopia?
Long
What corneal contour is associated with myopia?
Steep
What lens changes are are associated with myopia?
nuclear cataract, altered shape and position
What accomodation deficits are associated with myopia?
Spasm of near sighted vision
What axial length is associated with hyperopia?
Short
What corneal contour is associated with hyperopia?
Flat
What lens changes are associated with hyperopia?
aphakia (no lens), shape and position
Irregularities in what structures are associated with astigmatism?
Cornea and lens (lenticular)
What vision disorder does this test output represent:
+3.50
Hyperopia
What vision disorder does this test output represent:
+3.00, +1.50 x 90deg
Hyperopic astigmatism
What vision disorder does this test output represent:
-2.00, +1.00 x 180deg
Myopic astigmatism
What vision disorder does this test output represent:
-1.50, +2.20 x 45deg
Mixed astigmatism
What is refraction as a diagnostic tool?
It measures refractive error in vision
What does keratometry measure?
The corneal component of astigmatism
What is the criteria for screening for retinopathy of prematurity?
<1500 g (weight) or <30 weeks gestational age
What is the treatment for retinopathy of prematurity?
Diode laser retinal photocagulation, avastin
What physical exam findings can be associated with leukocoria?
strabismus, glaucoma, poor vision, orbital cellulitis, heterochromia
What is retinoblastoma?
A malignant intraocular tumor of retinal cell origin caused by a mutation of tumor suppressor gene RB1 on chromosome 13q1 (two hit model)
It presents with leukocoria (white reflex)
What is the treatment for retinoblastoma?
enucleation, chemotherapy, laser, cryotherapy
needs to be treated or it can metastasize to the optic nerve
What clinical features are associated with amblyopia?
- abnormal visual experience
- decreased visual acuity
- anatomic changes in the brain (striate cortex ocular dominance columns, decreased gray matter)
What are the treatment goals for strabismus? How is it treated in children?
- orthophoria (binocular vision)
- mono-fixationrange misalignment
Treatment: Eye patch over “good eye”
Until what age is eye patching useful to treat amblyopia?
9-10 years old
At what age should one perform congenital cataract surgery?
6 weeks
What is the purpose/goal of strabismus surgery?
Orthophoria, mobilization syndrome, improved stereopsis, improved appearance
What premature infants are at risk for retinopathy of prematurity?
low birth weight and earlier gestation age are two biggest risks; anemia and supplemental oxygen are risks as well
When does the embryonic fissure close?
6th week
What is a coloboma?
incomplete closure of the embryonic fissure
What are some causes of congenital cataracts?
hereditary, infectious (TORCH), metabolic disease, trauma, spordaic
