Common Causes of Vision Loss Flashcards
After a thorough history, what are the steps to an eye exam before calling a specialist?
- Visual acuity of each eye
- confrontation visual field testing
- extraocular motility
- pupillary reaction
- tonometry (pressure)
- ophthalmoscope
What are the 3 major categoty of causes of acute vision loss?
- media problems
- retinal problems
- neuroal visual pathway problems
What is the presentation of a patient with a corneal abrasion?
Causes?
How do you test for this?
Treatment?
- Presentation
- pain, redness, photophobia
- foreign body sensation
- cause - trauma or contacts
- Test
- fluorescein staining
- search for foreign body under the lid
- Treatment
- topical abx that cover pseudomonas (fluoroquinolone)
- cycloplegic drop cyclopentalate/atropie improves comfort
- NOT numbing drops
Why do you not send patient with a corneal abrasion home with numbing drops?
What are the numbing drops?
can erode cornea
proparacaine/tetracaine & topical NSAIDS
What does the fluorescein stain tell you?
intact epithelial cells do NOT take up the dye
it IS taken up by damaged epithelium
& you can visualize this with a cobalt blue light or Wood’s lamp
Who can prescribe topical steroids for an eye concern?
Why?
Eye doctor !
can cause infection to worsen
can cause elevated intraocular pressure & cataract
inhibit corneal epithelium
What is the key sign of allergic conjunctivitis?
itching
(usually bilateral)
Viral conjunctivitis shows what pattern of inflammation?
What lymph node is usually palpable?
follicular
preauricular
What is the presentation of a patient with viral conjunctivitis?
Treatment?
- Presentation
- watery or mucous discharge with swelling
- eye matted shut in the mornign
- starts in one eye & then “moves” to other
- recent cold symptoms
- Treatment
- WASH HANDS b/c very contagious
- typically self-limited (2-3 weeks)
- artificial tears, cool compress, OTC meds
- NO STEROIDS
What is the treatment for allergic conjunctivitis?
- Treatment
- OTC allergy medications
- artificial tears
- topical/oral antihistamines
- mast cell stabilizers
- cool compresses for swelling
What is the clinical presentation of a patient with bacterial conjunctivitis?
Treatment?
- Presentation
- copious mucopurulent discharge
- usually lack cold symptoms
- more likely to have papillary reaction
- Treatment
- topical antibiotics + referral to ophtho
- eye swab culture
- keep STI in mind - chlamydia & gonococcal need systemic treatment
Bacterial conjunctivitis shows what pattern of inflammation?
papillary
What is the clinical presentation of herpes keratitis?
- Presentation
- pain, redness, photophobia
- foreign body sensation
- recurrent
- dendritic staining
- follicular conjunctival reaction
- decreased corneal sensation
- Treatment
- refer to ophthalmologist
- topical / oral antivirals
- close monitoring
Herpes keratitis shows what pattern of inflammation?
How does it stain with fluorescein?
follicular
dendritic staining
What is Hutchinson Sign?
Treatment?
crusted blisters on the nose
implies herpatic involvement of nasociliary nerve & raises concerns about serious ophthalamic complications
- Treatment
- oral antivirals (most beneficial within 72 hrs)
- supportive treatment for complications by eye doctor
- systemic treatment by PCP for postherpetic neuralgia
What are the most common causes of infectious keratitis corneal ulcer?
Treatment?
bacterial (MC) - herpes/fungal/acanthamoeba
- Treatment
- history contact lens wear or eye trauma
- fluorescein staining
- urgent ophtho referral with cultures
- topical broad spectrum antibiotics, usully fortified
-
NO STEROIDS
- makes fungal & acanthamoeba worse
What is presbyopia?
cause?
what is the name of this theory?
age related farsigntedness
hardening of the lense - no longer able to change shape & thus focal point
Helmholtz Accomodation Theory
What percent of accomodation is present at age 40 compared to peak ability?
By 60?
- By 40- 50%
- by 60- 90%
What is Amblyopia?
“lazy eye”
brain fails to process inputs from one eye & over time favors the other eye
- Causes
- stabismus (MCC)- poo ocular alignment
- refractive error- ned glasses to better focus image
- Deprivational- ptosis, congenital catarac
What is the screening test for abnormal alignment?
Cover and Cover-uncover tests
What is a positive result on bruckner screening test?
Treatment?
deviated eye will have whiter/brighter reflex
glasses; eyepatch to force the use of the “lazy” ambylopic eye or penlalize the “good” eye
If visual pathway connections are not made by what age, vision will never be regained?
7-10yrs
What screening tests should be performed at a well-child visit?
- external inspection, pupil reflex, ocular motility
- corneal light reflex
- cover & cover/uncover testing
- bruckners
- visual acuity as soon as child able to cooperate
Myopia?
Hyperopia?
Astigmatism?
- Myopia - nearsightedness
- eye too long or cornea too steep
- concave lenses (-)
- Hyperopia - farsightedness
- eye too small or cornea too flat
- convex lenses (+)
- Astigmatism - abnormal cornea curvature
What are cataracts?
Causes?
Treatment?
when the lens gets cloudy as we get older
aging (MC) - trauma, radiation, congenital, steroid use, systemic disease (DM)
Treatment - surgery
What is the progression of vision loss with glaucoma?
Associated with what sign?
peripheral then central
associated with high pressure
What are the two major types of glaucoma?
- open angle (MC)
- fluid can’t go posterior, so it goes to the angle b/c the drain (trabecular meshwork) stops working as well as it used to
- closed angle
Why are screening exams for glaucoma so important?
early disease is typically asymptomatic
all vision loss from glaucoma is permanent
What are the primary risk factors for open angle glaucoma?
- increased intraocular pressure
- increased cup to disc ration
- increased age
- thinner central corneal thickness
- family history (6x in first degree relative)
- African ancestry (6x)
How do we diagnose glaucoma?
Treat?
- Diagnose
- check for visual field loss
- elevated IOP (10-21 normal)
- monitor optic nerve for increased cupping
- C:D > 0.5 or asymmetry
- Treament
- all targeting lowering IOP
- decrease aqueous production or increase outflow
- laser procedures
- all targeting lowering IOP
What are the medications & their MOA used to treat glaucoma?
- brimonidine (a2-agonist)
- decrease aqueous humor synthesis
- Timolol (B-blocker)
- decease aqueous humor synthesis
- acetazolamide (diuretic)
- decreas aqueous humor synthesis via carbonic anhydrase inhibition
- last effort before surgery b/c lots of side effects
- pilocarpine (chlinomimetics)
- used in emergencies to open meshwork and inrease outflow of aqueous humor
-
bimatoprost, latanoprost (prostaglandin analogs)- MC
- increase outflow aqueous humor
What is the leading cause of irreversible central vision loss among people > 50 yr?
age-related macular degeneration
What is the macula composed of & what is its major role?
higher concentration of cones centrally & is responsible for fine detailed central vision
What is “wet” macular degeneration?
yellow lipid & protein deposits (drusen) in deep layers of the retina, degenerative changes in the retinal pigment epithelium, choroidal neovascularization
What is the clinical presentation of a patient with age-related macular degeneration?
distortion (metamorphopsia) - straight lines are kind of wavy
eventual loss of central vision (scotoma)
What are the risk factors associated with age-related macular degeneration?
- age
- genetics
- female sex
- caucasian w/ light iris
- smoking
- hypertension
- hyperopia
- nutrition
What substances were found to reduce vision loss & progression in moderate/advanced AMD?
high dose antioxidants
smoking cessation & other lifestyle changes
What treatment was used to help with wet AMD?
anti-vascular endothelial growth factor intraocular injections
