Ophthalmology Clinical Correlation Flashcards
What is a subconjunctival hemorrhage?
Blood on surface of sclera (under conjunctiva) - no inflammation, pain or discharge harmless
- May be due to trauma, rubbing, may be spontaneous
- Dry eyes
- Lubricate, hot compress
- Harmless, resolves on own in 7-10 days
What are the big three that most opthamalogists spend their time seeing?
- Cataracts
- Macular Degeneration
- Glaucoma
What is a cataract?
Opacity of the normally clear lens cause by age, metabolic disorder, trauma or heredity
-Can be caused by trauma = shaken eye
How old are people with macular degeneration and what is it?
- Age related - any time after age 50, usually >70 years old
- Very common
- Causes decreased central vision
- Dry vs. Wet
- Nutritional Concerns
- 75-85
What does Dry Macular Degenearion Involve? Does it always affect vision?
-Drusen, pigmentary changes, pigmentary retinopathy & atrophy of retina
In minor cases, it may not affect vision, but may progress to affect vision later on.
What is macular drusen?
Calcified byproducts of cellular metabolism
What does exudative (wet) macular degeneration look like?
- Defects develop in deep retinal layers, growth of blood vessels under/in retina, edema and (sub-retinal) hemorrhage, eventual fibrosis/scarring and serious loss of vision
- Dry macular degeneration can lead to wet!
How do you treat dry macular degeneration?
Quit smoking, nutritional reccomendations, AREDS supplements, manage systemic diseases
How do you treat wet macular degeneration?
-All dry recommendations plus conventional laser, photodynamic therapy, anti-vegf drugs!
What is Glaucoma?
- Increased Ocular Pressure causes optic nerve loss
- Can be multifactorial
- Can occur at any age, but much more common over age 40
- Genetic predisposition in some
- Two main types: 1. Open angle
2. Closed angle
What is the treatment for Glaucoma?
Lower Eye Pressure!
-Medical, Surgical, Laser
What is the direction of aqueous flow?
Produced by cells in ciliary body ->around and through iris –> Trabecular meshwork –> Schemms canal –> Aqueous Vein –> Episcleral Vein
What does a normal optic nerve look like?
Pink, Good rim tissue, small central cup
What is optic nerve cupping? Why is the cup measured over time?
Enlarged cup due to loss of rim tissue that indicates loss of optic nerve fibers (Glaucoma!!)
- Larger cup/disc ration over time can indicate worse glaucoma
- Differnece in optic cup between two eyes may happen in glaucoma
What can drops cause?
Significant side effects!!
What do Glaucoma medications do?
Decreases intraocular pressure by decreasing aqueous production or increasing outflow.
Why is acute glaucoma (narrow angle) dangerous?
- Often its an eye emergency! (some ppl have intermittent symptoms - not flow blown attack)
- Acute onset
- Severe pain with loss of vision
- +/- nausea
- Red Eye
- Cloudy cornea
- EXTREMELY high ocular pressure >40 mmHg (eye feels like a rock)
- Usually caused by closure of previously narrow angle
What is OCT?
Optical Coherence Tomography
- Used to quantify optic nerve tissue
- Can show eye: open and closed angle glaucoma
- Can view macula and fovea health also
What are symptoms of acute angle glaucoma?
Pain, photophobia, blur, halo around lights
-Redness, Corneal edema, fixed/mid-dilated pupil, high IOP
What do you use to treat Acute Glaucoma?
- Pilocarpine
- Acetazolamide (Diamox)
- Sometimes with oral glycerine or isosorbide Icc/kg
- -> after treatment immediately refer to Ophthamology URGENTLY (surgical or laser peripheral iridotomy)
How does Pilocarpine work?
It causes constriction of the pupil and helps move the iris away from the angle.
- May not work right away, keep giving it!
- If IP is very high, there is too much resistance to arterial inflow to allow for adequate absorption
How does Acetazolamide work?
It is a diuretic that lowers pressure by “dehydrating” the eye.
What surgery is used to correct acute angle glaucoma?
Laser Iridotomy.
What is laser iridotomy?
It creates a hole through the base of the iris near the trabecular meshwork. It allows aqueous flow out and decreases pressure.
What systemic diseases need regular eye exams?
- Diabetes Mellitus
- Hypertension
- Cardiovascular Disease
- Thyroid Disease
What can diabetic retinopathy cause? How is it treated?
- Mild to severe forms
- Usually slowly progressive
- Can cause total blindness
- Treatment: Prevention: Managing blood sugar
- Laser therapy
- Surgical - vitrectomy
- Anti-vegf drugs
How does diabetic retinopathy cause leakiness in arteries of retina?
- Alterations in pericytes and basement membrane
- Microocclusions/collapsed artery 2. Leakiness
- Retinal Ischemia 3. Hemorrhages/exudates
- VEGF upregulation
- Angiogenesis
- Hemorrhage
- Organization
- Traction
What are the three stages of diabetic retinopathy?
- Nonproliferative diabetic retinopathy (NPDR)
- Preproliferative diabetic retinopathy
- Proliferative diabetic retinopathy (PDR)
What does NPDR look like in retina?
- Blot hemorrhages
- Cotton wool spots (edges - cloudy light areas)
- Microaneursyms (tiny red dots)
- Macular Edema (swelling of macula) - OCT scan - bubbles under
- Hard Exudates (white crust near end of artery –> cholesterol and fat that has leaked out of blood vessels - bright yellow deposits)
What can you see on the retina through a fluorescein angiogram of a diabetic patient?
You can see vessels and if bad, significant leakage/edema.
It shows microaneurysms.
-After insulin therapy it looks better
What does pre proliferative diabetic retinopathy look like?
- worse than NPDR
- Intraretinal vascular changes, venous bleeding, ischemic areas (cotton wool spots)
What does PDR (proliferative diabetic retinopathy) look like?
Neovascular (lots of vascularization) vitreoretinopathy, vitreous hemorrhage
-Very red all over, leakiness, large retinal hemorrhages
What is laser pan retinal photocoagulation (PRP)?
Hold contact like lens in eye and you laser all around periphery a lot.
- You’re wiping out the surrounding layers of the retina on the periphery so that the blood will resorb
- You put in 1,000-15,000 laser spots over a few visits
How often do diabetics need dilated eye exams?
Every year for Type II
After 5 years from diagnosis, every year for Type I
What is seen in hypertensive retinopathy?
- Narrowing and sclerosis of arterioles (arteriovenous nicking)
- Flame hemorrhages within retina
- Cotton wool spots (retinal micro-infarcts)
- Optic nerve edema in severe cases
- Disc edema, retinal edema, retinal hemorrhages, hard exudates, cotton wool spots, silver wired arterioles
How do you treat hypertensive retinopathy?
- Control blood pressure!!
- If significant vascular occlusions and ischemia, could require pan retinal photocoagulation
What are these:
- Amaurosis Fugax
- Migraine Scotoma
- Retinal Detachment
- Retinal Artery Occlusion
- Retinal Vein Occlusion
- Temporal Arteritis (Giant Cell Arteritis)
- Stroke
Causes of Sudden Visual Loss
What is amaurosis fugax?
- Sudden loss of vision in one eye
- Generally only lasts minutes
- Painless
- Etiology - usually temporary vascular insufficiency (Carotid Artery Disease until proven otherwise)
- Requires cardiovascular workup first!
- Requires Ophthalmology evaluation second
What is a retinal cholesterol emoli?
Yellow embolic material in arteriole of retina (hollenhorst plaque)
- Non-occlusive
- Warning sign of future disaster in vascular system - need to figure out where embolic material is coming from - can be very dangerous
- Workup includes Carotid Ultrasound and Echocardiogram
What is an ophthalmic migraine?
- With headache: classic (cephalgic)
- Without headache: cephalic
- Scintillating scotoma is the hallmark
- –Painless and temporary
- –Involves both eyes causing temporary hemianopsia (blocks vision)
- –Usually lasts 20-30 minutes
- Etiology: spasm of arteriole in the occipital cortex
What is the treatment for migraine?
- Examine for visual loss or ocular pathology
- Reassurance
- Consider preventative therapy if attacks are frequent
- Consider physical examination and work-up if attacks are frequent or atypical
What is retinal detachment?
- Sudden partial vision loss in one eye
- Painless
- May be progressive, always sustained (does not resolve on its own)
- Often accompanied by floaters and photopsias
- Higher frequency in myopia
- Etiology - Usually spontaneous, can be associated with trauma
- Treatment: refer immediately to ophthalmology for surgery
How can you try to prevent/slow retinal detachment?
- Can laser a tear
- Use Scleral buckling which decreases the diameter of the eye and makes it easier to push the retina back on
What is retinal arterial occlusion?
- Sudden severe loss of vision in one eye
- Painless
- Vision loss usually permanent, but may recover if treated rapidly
- Cherry red spot indicates acute central retinal artery occlusion
What does a cherry red spot indicate?
- Acute central retinal artery occlusion
- It is a pale retina with a red fovea (rest of retina is pale and swollen)
What does a white, swollen upper part of the retina indicate?
- Branch retinal artery/partial retinal artery occlusion
- Patient will notice half of vision missing
What happens in an acute arterial occlusion?
Embolus blocks retinal circulation - Treatment is urgent!!
How do you manage Acute Arterial Occlusion?
- Rebreathing CO2 in paper bag
- Timolol or levobundolol to lower intraocular pressure –> decreasing aqueous humor production
- Intravenous acetazolamide (Carbonic anhydrase inhibitor -> decreases aq. humor production- dec. osmotic flow)
- Massaging of globe with lids closed
- Refer to Ophthalmology
What does an acute arterial occlusion look like?
Plaque spot on the retina and edema.
What is retinal vein occlusion related to?
-More common in hypertension and diabetes
What are important facts about retinal vein occlusion?
- Central (CRVO) or branch (BRVO)
- Prognosis guarded for central vein occlusion, with risk of neovascular glaucoma - requires Ophthalmology referral (not as urgent)
- Treat underlying systemic diseases and rule out hyper coagulable states
What does Central Retinal Vein Occlusion look like on the retina?
“Squashed tomato”
What is temporal arteritis (giant cell arteritis)?
- Headache and scalp tenderness
- Fever, weight loss
- Jaw claudication
- Polymyalgia rheumatica
- Vision loss secondayr to inflammatory vaso-occlusion . . .retinal arteriolar occlusion or optic nerve infarction
- Vision loss can be sever involving one or both eyes
- May result in total blindness
- Rarely complicated by aortic aneurysm or stroke
How do you diagnose temporal arteritis?
STAT Erythocyte Sedimentation Rate (ESR) and C-reactive protein (CRP)
—Schedule temporal artery biopsy to look for PMNs in the arterial wall within 2 weeks
How to treat temporal arteritis?
Start high dose systemic steroids!! IMMEDIATELY!
-Even before you get test results, patient is at risk of loss of vision from other eye
What does temporal arteritis show in a section?
- Inflammation of arterial wall
- Fragmentation/disruption of the internal elastic lamina
- +/- multinucleate giant cells
- Skip lesions (therefore often missed in biopsy) - have to section a long piece of the artery
What happens in a visual cerebrovascular accident?
- Sudden painless loss of vision causing bilateral hemianopsia
- Usually involves the occipital cortex, but can occur anywhere in visual pathway
- Visual loss occurs bilaterally on the contralateral side of a cortical lesion
What could a stroke of the right occipital cortex cause?
Left homonymous hemianopsia (can’t see left visual field)
