Flashcards in Pathology of the Eye Deck (62):
Why is retinal detachment an urgent problem?
loses blood supply and tissue can die
Where is the largest concentration of cones in the eye?
What are the 3 visual fields?
Total visual field with both eyes: 170 degrees
Total monocular visual field: 150
Total binocular visual field: 120
misalignment of eyes
misalignment of eyes when fusion is broken
What is the function of the eyelids and eyelashes?
protection and lubrication of the cornea
Mucous membrane that lines the inside of the eyelids and some of the front of the eye
What is the function of the cornea? What aspect is most responsible for this?
Most external refractive media of the eye (it is avascular)
Curvature of the cornea contributes to amount of refractive error and astigmatism
Contact lenses are placed over the cornea
What are some functions of the anterior chamber and the angle?
Part of the refractive media
Holds the aqueous humor
Nourishes the cornea, maintains the pressure of the eye
Angle contains the structures that regulate the outflow of the eye
Affected by glaucoma, uveitis, neovasculature
What does the iris control? why are eye exams done in dark lighting
light into the eye
dilate pupils in dark room
Inflammation of the
HLA related, arthritis,
What 2 problems can occur with the lens with aging?
With age, the lens naturally hardens and yellows --> cataract formation (blur, glare, distortion)
and ability to accommodate
What are myopia, hyperopia, astigmatism and presbyopia? how are all of these treated?
Presbyopia-loss of accommodation
*all corrected by lenses
Where is the largest concentration of the cones in the eye?
Posterior Vitreous Detachment
Most common cause of “flashes or floaters”
Usually benign age-related
May cause retinal hemorrhage, retinal break, vitreous hemorrhage
What can cause poor binocular vision?
Poor monocular visual acuity
Poor monocular/binocular visual fields
What is a common cause of viral red eye? What are the symptoms?
Most common type of infectious red eye
Associated with upper respiratory infection
May have fever
Usually starts unilateral --> bilateral
Likely have ocular irritation
Superficial punctate keratitis (SPK) on exam
Diffuse redness, “pink”
What eye problems can steroids cause?
elevated intraocular pressure (IOP)--> glaucoma
What are some common causes of bacterial red eyes?
Causes: S. aureus, S. epidermidis, Strep pneumonia, H. influenza
Mucopurulent discharge, esp upon waking
RED eye, red in fornices
Usually no corneal involvement except if severe
What is blepharitis? What normally causes is?
dry, flaky eyes
usually caused by:
*Inflammation of meibomian glands
Limited lacrimation-Sjogrens, lacrimal gland tumor
bilateral and chronic
What are the causes, symptoms and treatment of Subconjunctival Hemorrhage?
Causes: Trauma (even mild), valsalva, HTN, bleeding disorders, antiplatelet/anticoag tx
symptoms: “Bruise” of the eye
BRIGHT RED eye, often sectoral
NO vision changes, NO pain, NO discharge
Tx: nothing for the hemorrhage but look into work up of the cause
What are causes, symptoms of anterior uveitis? How is it treated?
Causes: idiopathic, trauma, HLA-B27 associated, post operative, many more
Pain! Photophobia (hallmark), redness, tearing, blur
Diffuse injection, esp perilimbal
Cells and flare in the anterior chamber
tx: Refer to eye doctor!
High doses of topical steroid and cycloplegics
What causes Acute Angle Closure Glaucoma? Signs and symptoms?
closed iridocorneal angle-->Blocks outflow of aqueous humor
PAIN! Headache, significant blur, nausea/vomiting
*acutely high intraocular pressure (IOP), Unreactive pupil, corneal edema, closed angle
When do you need to refer a red eye to an eye doctor?
No improvement within 3 days of treatment
Unsure of cause
What is the leading cause of blindness globally?
What is done to treat cataracts?
simple outpatient surgery -->
Removal of opacified lens
and insert an implant (IOL)
What are the 3 most common types of cataracts?
brownish in center
Symptoms: blur, myopic shift, possible glare
Symptoms: glare, later blur
Posterior subcapsular (PSC):
between capsule and lens
usually from DM and steroids**,
Age, trauma, intraocular surgery
What is the most common cataract? What are some symptoms?
Age related cataract
Often a combination of lens opacities
BLUR-usually so slowly progressive that the patient is only mildly aware
What is the leading cause of blindness in the US for over the age of 55? what are the causes? some risk factors?
Age-related Macular Degeneration
risk: AGE, smoking, family history, vascular disease, Northern European ancestry
What vision is lost in Age-related Macular Degeneration?
center vision lost
peripheral vision still in tact
what defines dry vs wet macular degeneration?
Dysfunctional RPE (Retinal Pigment Epithelium) does not clear waste debris so the waste (drusen) clumps underneath--> RPE atrophies
90% of cases
(dry normally progresses to wet)
wet=choroidal neovascularization present because of stress to choroidal circulation to try to get rid of waste
New blood vessels develop and bleed
Usually dramatic change in vision or visual distortions occur
What can the pinhole show?
there is a refractive component
What is acute vs chronic glaucoma?
damage to the structure of the optic nerve
Most cases are chronic
Slowly progressive, over many years
Angle closure-SEVERE, emergency
Secondary open angle
Extreme IOP increase
Usually won’t cause quick damage to optic nerve head and subsequent severe loss of vision
What is the most common type of glaucoma? What are some characteristics? What is the goal in management?
Primary Open Angle Glaucoma
Usually elevated IOP
Glaucomatous optic nerve
Visual field loss (normally only later in the dx)
goal: prevent visual field loss (decrease the IOP)
What is more effective in treating glaucoma, topical or oral meds?
What glaucoma could cause a red eye?
angle closure glaucoma
What type of glaucoma is likely to cause an acute attack?
narrow angle glaucoma suspect
(steroid will take a long time to affect the eye)
What can cause retinal hemorrhages (vascular problems) in the eye?
diabetic retinopathy, hypertensive retinopathy (or artery/vein occlusions), anemia retinopathy
*focus most on DM and hypertension
What are the diabetic eye diseases?
Unstable refractive error
-->Changes in water content of lens
Cranial nerve palsies
-Proliferative (including of the iris)
What are the risk factors for diabetic retinopathy?
DM for over 10 years (type I or II)
Chronic hyperglycemia (HbA1c >8%)
What symptoms do most people with diabetic retinopathy have?
usually no symptoms
may have: blur, or flashes/floaters
What is the lowest state of diabetic retinopathy?
Mild Nonproliferative Diabetic Retinopathy
-Loss of pericytes
What happens in Moderate/Severe Nonproliferative Diabetic Retinopathy?
-capillary occlusion and non-perfusion
-veins start to be affected---> venous bleeding
-cotton wool spots (microvascular infarcts)
-intraretinal macrovascular abnormalities--> form collateral networks
also, no treatment. monitor
What is proliferative diabetic retinopathy? What is the treatment?
new vascularization==> BAD
can cause retinal detachment of vitreous hemorrhages
Tx: laser photocoagulation or vitrectomy
What is diabetic macular edema? What is the treatment?
Leakage of fluid and exudates in the macula
Most common cause of visual impairment
Laser-direct and grid
What can hypertensive retinopathy cause? Will it cause noevascularization?
-->Flame shaped Hemes
-Cotton wool spots
*will NOT cause neovascularization on its own
What are different types of retinal plaques?
From carotid arteries
From cardiac valves
Dull white, non-occlusive
From carotid arteries
can cause blockage in the eye or no symptoms
What will happen due to artery occlusion? what can cause this?
acute vision loss
significant pupil defect in the affected eye
Cause: embolism from heart or carotid artery; atherosclerosis, giant cell arteritis
What can happen with a vein occlusion? What are the likely causes?
blood backed up==> get really ugly bloody retina
caused by DM*, HTN*, blood dyscrasias
What is papilledema? What are the differentials?
swollen in both optic nerves coming from something behind the eye causing an increase in intracranial pressure
Malignant hypertension, tumor, pseudotumor cerebri, bilateral ischemic optic neuropathy, bilateral optic neuritis
What is Ischemic optic neuropathy?
Infarction in the ON, can be segmental--> rare to have in both eyes at the same time
Etiology: HTN, DM, arteriosclerosis, hyperlipidemia, giant cell arteritis
Permanent loss of visual function*
What is optic neuritis?
Inflammation of ON
Etiology: idiopathic, multiple sclerosis, severe infection, inflammation
Many have full return of visual function*
What eye condition can happen from inflammation/immune system associations? What is the most common?
uveitis (anterior=most common)
(conjunctivitis is NOT normally)
What are some ocular urgency symptoms?
Trauma (foreign body or head trauma)
Sudden vision loss
What are some conditions that are ocular urgencies?
What does transient vision loss normally indicate?
loss of blood flow
cardiac problem/circulation problem --> normally a brain, not an eye issue
vision normally returns within 24 hours
what normally causes Acute Permanent Vision Loss?
vision loss for >24 hours
usually vascular but can also be optic neuropathy or retinal detachment as well
What normally causes flashes? What normaly causes floaters?
Usually caused by objects anterior to the retina
most common causes: Posterior Vitreous Detachment
What is a retinal break?
Retinal tear, retinal hole, retinal dialysis
Defect in the retina where the retina has pulled away from the RPE
Precursor to RD in many cases
When do you test for Retinal Detachment?
Anyone with “flashes and floaters” MUST have a dilated retinal exam to rule out Retinal Detachment
Lattice degenerationretinal break
tx: laser photocoagularion, scleral buckle and cryotherapy
What can cause ocular pain?
Effects of trauma
Corneal abrasion, etc
Angle closure glaucoma
--> need to find the cause to treat