Ocular Disorders

Optometry vs Opthalmology vs Optician

optometry→healthcare professional
-complex optic cases
-advanced optic devices

opthalmology→MD
-mx care+surgery
-medical school+residency

optician→eyeglasses
-opticianry school/apprenticeship

Path of Light

1. light

2. cornea

3. lens

4. retina

5. optic nerve

6. optic tracts

7. occipital lobe

Cornea

transparent structure that refracts light

Iris

colored part

blocks excess light from coming in

Pupil

opening in the middle of the iris

controlled by muscles in the eye (opens+narrows iris)
-light→constriction
-dark→dilation

Lens

focuses light into retina

Retina

processes visual information (phototransduction)

components

cones
color
light
detail
-macula
-fovea

rods
motion
dim light
peripheral vision

Optic Nerve

passes light+information from eye to the brain

Optic Nerve Tract

optic nerve→optic chiasm (crosses over to other lobe)→optic tract→occipital lobe

Myopia (Nearsightedness)

PP: eye grows too deep/far back into skull

RF: glaucoma
retina detachments
cataracts
macular degeneration
legal blindness

E: m/c→worldwide epidemic

CM: near→clear vision
far→blurry vision

TX: glasses(no lenses)
contact lenses
myopia management

Hyperopia (Farsightedness)

PP: eye is too short→light passes past/through eye

RF: narrow angle glaucoma

CM: near→blurry vision
far→clear vision

TX: glasses+lenses
contact lenses

Astigmatism

PP: refractive lens error→problem with how eye focuses light
not a dx

E: misshapen cornea
misshapen lens

Presbyopia

PP: lens stiffens→decreased accommodation to light

E: ~40 y/o
age-related

CM: near→blurry vision
headaches
eye strain
tired eyes

Congenital vs Acquired Color Blindness

can’t see certain colors

congenital
x-linked recessive
males→7%
females→0.5%
bilateral
m/c→red-green
mother needs to be colorblind/carrier in order to have colorblind son

acquired
retina dx
optic nerve dx

Dark Adaptation

ability to adapt to different illuminations/brightness levels

modulated by rods+cones
-cones are faster than rods

poor dark adaptation etiology
aging
posterior segment ocular dx
-genetic
-acquired
poor diet→vitamin A deficiency

Blepharitis

E: demodex mites in hair follicles
s aureus
epidermidis

CM: erythema
irritation
gritty feeling

TX:
mites→lotilaner eye drop

bx+mites:
tea tree oil
hypochlorous acid spray cleaner

Entropion

PP: eye lid turns inward→eyelashes irritate eye

E: m/c→involutional (skin shrinking with age)
trauma
congenital
tumor
infection
-lower eyelid (m/c)

CM: can’t see eyelid

Ectropion

PP: eyelid turns outward→eyelid+eye exposed

E: m/c→involutional (skin shrinking with age)
tumors
trauma
7th nerve paralysis
congenital
-lower eyelid (m/c)

CM: red portion of lower eye

Hordeolum vs Chalazoin

hordeolum

• active lesion

• new

• painful

• lower eyelid

• “stye”

TX: warm compress
PO abx

chalazoin

• inactive lesion

• long standing

• no pain

• upper eyelid

TX: warm compress
intense pulsed light therapy (IPL)
surgical excision

Preseptal vs Orbital Cellulitis

preseptal
erythema limited to the eyelid

TX: PO abx

orbital
erythema surrounds whole eye
limited ocular movement
decreased vision
chemosis (swollen conjunctiva)
proptosis (eyes pop out)

TX: IV abx

Dacryoadenitis

PP: inflammation of lacrimal gland

E: m/c→inflammation
mumps
mono
influenza
bx (rare)

CM: erythematous tender swelling of outer 1/3 of upper eyelid

TX:
NP: cool compress
calm inflammation

MX: abx
steroids

Dacryocystitis

PP: inflammation of lacrimal sac

E: bx infxn
nasolacrimal duct obstruction
tumor

TX: warm compress
abx

Ptergyium

PP: fibrovascular tissue from conjunctiva→cornea→dry eye/astigmatism

E: UV exposure
chronic irritation

CM: wing-shaped fold on eye

Pinguecula

PP: noncancerous growth of the conjunctiva→dry eye

E: UV exposure
chronic irritation

CM: white-yellow growth on conjunctiva of eye

Bacterial Conjunctivitis

E: s aureus
s pneumonia
h influenzae
gonorrhea
chlamydia

CM: unilateral/bilateral
mucopurulent discharge
open eyes→“glued shut”
discomfort

TX: topical abx eye drops (gtts)

Viral Conjunctivitis

E: adenovirus
URI virus

CM: foreign body sensation
discomfort
red eye+watery discharge
UL→BL

TX: no eyedrops (gtts)
referral→betadine rinse
preservative free artificial tears
steroid eye drops

Allergic Conjunctivitis

E: type 1 hypersensitivity rxn
type 4 hypersensitivity rxn

CM: bilateral at same time
itchy
discomfort
swelling+puffy-eyed appearance

TX: pataday
alaway
zaditor
lastacraft

Subconjunctival Hemorrhage

PP: rupture of conjunctival vessels

E: trauma
sneezing
coughing
vomiting
straining

TX: self limiting
stop NSAIDS
stop anticoagulants

chronic:
coagulation DX
HTN

Herpes Zoster Opthalmicus

PP: dendritic/pseudodendritic lesions on cornea

E: varicella zoster virus

DX:
slit lamp exam+NaFL stain+lissamine green/rose bengal stain

TX:
PO acyclovir x within 72 hrs
PO valacyclovir x within 72 hrs
2nd infxn prophx→topical abx eye drops (gtts)
immunocompromised→admit+IV acyclovir

Dry Eye Disease

PP/E: mimic for eye conditions

CM: bruning
itching
redness
tearing
foreign body sensation
gritty feeling
blur→clears with blinking

TX: depends on type of dry eye

Uveitis/Iritis

PP: inflammation of choroid+ciliary body+iris

E: idiopathic
autoimmune
inflammatory

CM: UL or BL
red
painful
light sensitive

TX: topical steroid
pain→cycloplegic
referral

Cataracts

PP: clouding of the lens (behind iris+pupil)→vision loss

E: m/c vision loss over 40+ y/o
#1 cause of blindness worldwide
age
UV light
DM
smoking
injury
steroids

CM: blurry vision (even with glasses on)
glare
decreased color brightness

TX: cataract extraction surgery

Primary Open-Angle Glaucoma

PP: increased eye pressure→optic nerve cell death

RF: 65+ y/o
black
DM
myopia
ocular HTN (IOP 21+ mmHg)
larger cup→higher risk

E: leading cause of visual impairment/blindness in US
2.5 million
50% unaware

CM: gradual loss of peripheral vision
no pain

DX: optic cup enlargement
high eye pressure

TX:
beta blocker drops
prostaglandin drops
carbonic acid inhibitor drops
alpha agonist drops
surgery

Primary Closed-Angle Glaucoma

PP/E: iris blocks exit of aqueous humor from anterior chamber→increased intraocular pressure→optic nerve cell death

RF: larger cup→higher risk

CM: intense ocular pain
blurred vision
halos around lights
nausea
vomiting

DX: diffuse conjunctival injection
dilated+fixed pupil
clouding of cornea

Posterior Vitreous Detachment

PP: gel surface that attaches on to retina (vitreous)→detaches from retina

CM: asx
or
floaters
flashes of light

DX: discrete translucent/broken circle shaped opacity near optic disc
retinal break (8-10%)→dilated eye exam

Vitreous Hemorrhage

E: vitreous detachment
DM
retina break/detachment
sickle cell dx
retinal vein occlusion
macular degeneration
trauma
tumor
etc.

CM: sudden+painless vision loss

TX: stop blood thinners
no heavy lifting
vitrectomy

Retinal Hole/Tear/Detachment

RF/E: high myopia (nearsightedness)
retinoschisis (split retina)
neoplasms
vascular dxs
trauma
etc.

CM: flashes
floaters
curtain/veil over vision
vision loss

TX: urgent retinal specialist referral→surgery

P: macula on→better vision prognosis→more of an emergency

Diabetic Retinopathy

RF: high blood sugar
DM length

E: leading cause of blindness in US
proliferative vs non-proliferative
-mild
-moderate
-severe

CM: vision fluctuations
floaters
vision spots
shadow in vision
distorted/blurry vision
slow healing eye lesions
diplopia
macular edema

TX: depends on severity

Hypertensive Retinopathy

CM: asx
or
decreased vision
artery narrowing

severe:
hard exudates
flame-shaped hemorrhages
optic nerve edema

TX: control BP

Macular Degeneration

PP: part of retina deteriorates→can’t remove waste

RF: age
FHx
cigarette smoking

E:
dry→gradual breakdown of cells in macula
wet→new abnormal blood vessels grow under central retina→leaking+bleeding+scarring
-exudative
-neovascular

CM: decreased/blurry central vision
slow dark adaptation

DX:
dry:
macula→drusen

wet:
retinal exudates
neovascularization

TX:
wet→retina specialist referral→anti-vegf injections
vision loss→low vision services