vision loss Flashcards
myopia vs hyperopia
myopia: nearsighted; hyperopia: farsighted
amblyopia
lazy eye
painful vision loss is associated with what condition
glaucoma
what is the first thing you should do when starting a physical exam of the eyes
visual acuity
the complete eye exam: 8 steps
- visual acuity
- confrontational visual fields
- pupils
- extraocular movements
- external (ptosis)
- tonometry
- slit lamp (pen light) exam
- dilated fundus exam
how do you perform confrontational visual field testing
brings a test object from a non-seeing area (such as behind the head) into the field of vision. You will be asked to focus your eyes on a central point—such as the examiner’s nose ,and tell the examiner when you first see the object enter your visual field
how do you check for afferent and efferent pathways of eyes
afferent: pupil reactivity
efferent: equal pupil size
- if you shine the pen light in eye A and nothing happens to eye A; shine the light in eye B to check for consensual constriction. If there is consensual constriction, then the efferent pathway is functional
- Now shine the light in eye A again and check for consensual constriction. If there is none; the afferent pathway is the problem
what does a relative afferent pupillary defect (RAPD) detect
A positive RAPD means there are differences between the two eyes in the afferent pathway due to retinal or optic nerve disease.
how can you test for a relative afferent pupillary defect (RAPD) detect
swinging flashlight test
- In a normal swinging light test (i.e. there is no RAPD) the pupils of both eyes constrict equally regardless of which eye is stimulated by the light. In an abnormal swinging-light test (i.e. there is a RAPD) there is less pupil constriction in the eye with the retinal or optic nerve disease
where does the macula sit in relation to the optic disc
temporally
in a dilated fundus exam, what are you looking for
- nerve (disc edema/pallor; cupping)
- macula (heme, exudate; cotton wool spots)
- Vessels
- periphery (retinal detachement)
what dilating drops can you use for a dilated fundus exam. Name in order of increasing duration of action
- phenylephrine
- tropicamide
- cyclopentolate
- atropine
what are cataracts
any opacity of the crystalline lens
- age-related
- congential/traumatic
clinical presentation
- gradual, chronic, painless loss of vision
- glare, especially at night
- PE: decreased visual acuity; yellowing/opalescent changes to the lens
Cataracts
management of cataracts
ophthalmology referral: if lifestyle is affected
- glasses
- surgery (phacoemulsification)
- prognosis: excellent
what are the 3 primary components of Glaucoma
- intraocular pressure increase
- optic nerve damage
- visual field loss
what are the 2 primary subtypes of glaucoma
- acute angle closure glaucome (emergency)
- primary open angle glaucoma
cause of open angle glaucoma
decreased aqueous outflow resulting in increased intraocular pressure
clinical presentation
- early symptoms: asymptomatic
- late: chronic, painless vision loss
- peripheral first
- central late
- PE: increased cup/disc ratio; visual field loss
Glaucoma open angle
management of glaucoma
- ophthalmology referral
- topical anti-ocular hypertensives
- laser trabeculoplasty
what is retinal detachment (RD)
seperation of the retinal layer from the underlying choroidal (vascular layer)
name the two types of retinal detachment (RD) and the diseases they are associated with
- Rhegmatogenous RD: myopia
- Tractional RD: Diabetes
clinical presentation
- floaters
- Photopsias (light flashes)
- Loss of vision
- progressive scotoma
- curtain-like
- PE:
- +/- decreased vision
- may be peripheral only
- raised, whitish retina
- posterior vitreous detachement
- +/- decreased vision
retinal detachment
treatment for retinal detachment (RD)
- ophthalmology referral
- Medical: laser retinopexy; air bubble tamponade
- Surgical: vitrectomy
* prognosis: variable
what is macular degeneration
degeneration of photoreceptors and their supporting structures
- # 1 cause of legal blindness in western world
Clinical presentation
- gradual or acute blurred vision
- Metamorphopsia (wavy, distorted vision)
- Central Scotoma (blind spot)
- PE: +/- decreased vision; Amsler grid distortion
age-related macular degeneration (ARMD)
distinguish between dry ARMD and wet ARMD
- Dry
- happens first
- Drusen, pigment mottling
- geographic atrophy
- Wet
- subretinal fluid, blood, new vessels
management of age-related macular degeneration (ARMD)
- ophthalmology referral
- vitamins (antioxidants/zinc)/omega 3 FA
- stop smoking
- daily amsler grid
- intravitreal steroid
**prognosis: variable
what is the difference between central retinal artery occlusion and central retinal vein occlusion
central retinal artery occlusion: embolic
central retinal vein occlusion: thrombotic
clinical presentation
- acute, total, painless loss of vision “black as night”
- PE: “no light perception,” afferent pupillary defect, whitening of retina, “cherry red spot”
central retinal artery occlusion
clinical presentation
- acute, variable, painless loss of vision
- PE: variable vision; +/- afferent pupillary defect; “blood and thunder” retinal appearence
central retinal vein occlusion
treatment and prognosis of central retinal artery occlusion and central retinal vein occlusion
both: refer to ophthalmology
- CRAO: poor
- CRVO: variable
clinical presentation
- asymptomatic
- PE: systemic HTN; characteristic fundus findings
hypertensive retinopathy
Give Keith-Wagener-Barker classification of hypertensive retinopathy for Group 1
- arteriolar narrowing
- “copper wiring”
- arteriolar sclerosis
- silver wiring
Give Keith-Wagener-Barker classification of hypertensive retinopathy for Group 2
(group 1, plus)
- arteriolar narrowing
- “copper wiring”
- arteriolar sclerosis
- silver wiring
- A:V crossing changes
- A:V nicking
Give Keith-Wagener-Barker classification of hypertensive retinopathy for Group 3
(Group 2, plus)
- cotton wool spots
- retinal hemorrhages
- retinal edema/edudation
- macular star
Give Keith-Wagener-Barker classification of hypertensive retinopathy for Group 4
(group 3, plus)
- disc edema
managment for hypertensive retinopathy
- systemic blood pressure control
- ophthalmology referral if associated with vision loss
what is the #1 cause of blindness in western world in patients less than 50 yo
diabetic retinopathy
name the 2 basic components of diabetic retinopathy
- non-proliferative/proliferative diabetic retinopathy: progressive retinal ischemia
- diabetic macular edema: increased vascular permeability
What do non-proliferative and proliferative diabetic retinopathy have in common? What differentiates them?
- Both
- microaneurysm
- dot-blot hemorrhages
- cotton wool spots
- venous bleeding
- Proliferative diabetic retinopathy only
- neovascularization
what fundoscopic findings indicate macular edema often seen diabetic retinopathy
- graying/slight opacification
- microaneurysm
- hard exudate
treatment for diabetic retinopathy
- blood sugar control
- ophthalmology referral
