ophthalmic lecture Flashcards
anterior segment contains
orbits, lids/lashes, cornea, conjunctiva,sclera, anterior chamber/aqueous humor, iris, pupil
posterior segment
posterior vitreous, optic nerve, macula/fovea, peripheral retina, vessels (arteries and veins)
segment b
lens and ciliary body
LR6 +SO4+EE3
lateral rectus CN6 (abducens)
superior oblique CN 4 (trochlear)
everything else CN3 (oculomotor)
meibomian glands purpose
secrete the oil layer to our tear film, oil prevents tears from evaporating
the cornea is filled with
thousands of tiny nerve endings that make the cornea extremely sensitive to pain.
The pathway for the outflow of aqueous humor.
Aqueous humor produced by ciliary body -> flows through the pupil into the anterior chamber -> flows out through the trabecular meshwork into the canal of schlemm -> absorbed into the episcleral veins via the collector channels.
macula is in charge of our
central vision
also contains pigmented cells called cones
optic nerve is in charge of
our peripheral vision
periorbital (preseptal) cellulitis
define
s/s
tx
- Bacterial infection of eyelid anterior to orbital septum that occurs 2° to sinusitis, trauma, ocular Sx, hordeolum, etc.
- s/s = eyelid tenderness, erythema, and edema; (-) proptosis, (-) pain on EOMs, (-) vision changes
- Tx = Mild = PO Abx (amoxicillin, Bactrim); moderate - severe = hospital admission + IV Abx (vancomycin, clindamycin, cefotaxime)
orbital (septal) cellulitis
define
s/s
tx
- Bacterial infection that occurs Most commonly 2° to sinusitis
- s/s = eyelid tenderness, erythema, and edema; (+) proptosis (bulging), (+) pain on EOMs, (+) decreased vision
- Tests = assess EOMs, CT scan (infection of the orbital fat and EOMs), CBC with diff
- Tx = hospital admission + broad spectrum IV abx
dacrocytitis
bacterial infection of the lacrimal sac
most common is staph aureus
dacrocytitis s/s
pain, erythema and edema over lacrimal sac/medial canthus (nasal side of the lower lid)
orbital blowout fractures
the force from a direct traumatic blow to the eye, - a fracture of thin bones of the orbital floor
orbital blowout fracture complications
the contents of the orbit EOM, fat ect, can get entrapped which leads to the following :
decreased visual acuity, diplopia (especially upward gaze if there is inferior rectus entrapment), restricted eye movement, ptosis
orbital blowout fracture s/s
pain, tenderness, orbital emphysema (eyelid swelling after blowing nose), ecchymosis
ectropion
eyelid turned outwards
most common in elderly and aging
ectropion s/s & tx
- irritation, tearing (epiphora), foreign body sensation
- artificial tears, blepharoplasty
entropion
eyelid turned inward
most common in elderly and aging
entropion s/s & tx
irritation, tearing (epiphora) foreign body sensation, corneal abrasions- leads to pain and vision changes
tx: artificial tears and blepharoplasty
hordeolum-internal
inflammation/bacterial infection of a meibomian gland
hordeolum-external
inflammation/bacterial infection of the glands of zeis
horeolum s/s &tx
pain, tender, warm, erythematous, swollen, soft, lump on eyelid
-hot compress, topical abx (erythormycin or bacitracin)
chalazion
caused by chronically blocked meibomian gland
-untreated horeolum is a chalazion
chalazion s/s &tx
nonpainful, nontender, swollen hard lump on eyelid
hot compress, eye hygein and if not resolving IND
blepharitis
inflammation of both eyelids involving the skin, lashes and meibomian glands
blepharitis s/s and tx
crusting on lashes, red-rimming/erythema of the eyelid, burning irritation, tearing, foreign body sensation
tx: hot compress, eyelid/lashes scrubbing, baby shampoo, messaging of meibomian gland
viral conjunctivitis
most common pathogen- adenovirus- thus typically occurs with a URI
source: swimming pool
most common seen in kids
viral conjunctivitis
s/s
tx
foreign body sensation, watery discharge, bilateral, no vision changes, preauricular lymphadenopathy, conjunctival injection
tx: supportive
bacterial conjunctivitis
most common pathogen staph aureus, strep pneumoniae
bacterial conjunctivitis
s/s
tx
purulent discharge, a lot less conjunctival injection, crusting on lashes, no vision changes, unilateral eye matted shut in the morning
tx: abx drops
if contact lens wearer cover pseudomonas w/ FQ (ofloxacin)
allergic conjunctivtis
h/o seasonal allergies
s/s cobblestone mucosa to the inner eyelids, itching, bilateral
tx antihistamine drops ketotifen, olopatadine
pingurcula
yellow elevated conjunctival nodule nasally
*does not grow but can get inflamed/cause irritation
no vision changes
subconjunctival hemorrhage
subconjunctival bleeding due to broken vessels
most commonly from heavy lifting, sneezing, valsalva
pyerygium
elevated fleshy vascular triangular shaped mass extending onto the cornea
can be nasal and temporal in origin but most commonly nasal
-tx: artificial tears, sunglasses and surgery if grown into visual axis
corneal abrasion
scratched eye, foreign body
s/s blurred/decreased vision, pain, tearing, photophobia, foreign body sensation
corneal abrasion pain relief with
propericaine drops
**do NOT rx
corneal abrasion tx
abx drops that cover pseudomonas in contact lens wearers, bandage contact lens
bacterial corneal ulcer
causes pseudomonas (in CL wearers) and acanthamoeba
bacterial corneal ulcer
s/s
tx
pain, photophobia, reduced visual acuity, tearing, hazy cornea, +/-hypopyon, ulceration on fluorescein, discharge conjunctival injection, ciliary injection
tx- FQ abx drops- ofloxacin, moxifloxacin DO not place on a BCL
viral corneal ulcer
cause: HSV h/o cold sores or previous HSV keratitis s/s pain photophobia, tearing & decreased visual acutiy slit lamp: dendritic tx: PO acyclovir
herpes zoser ophthalmicus
causes: herpes zoster (shingles)
s/s painful vesicular rash along CN V dermatome, eye pain, decreased visal acuity, hutchingson’s sing (lesion on nose=ocular involvment)
Uveitis anterior
inflammation of the iris or ciliary body
-unilateral ocular pain, injuection, photophobia and decreased vision
uveitis posterior
inflammation of the choroid (a pigmented vascular layer between the retina and sclera)
-blurred/decreased vision, floaters, no pain
uveitis causes
a) granulomatous uveitis seen in: sarcoidosis, tuberculosis, syphilis, leprosy
b) non-granulomatous uveitis seen in: ankylosing spondylitis, reactive arthritis, rheumatoid arthritis, lyme disease
uveitis tx
refer, topical steroids, topical cycloplegic, PO steroids, glaucoma drops due to steroids causing elevated IOP
cataract description
Inside our eyes our natural lens made up of water and protein helps us see. As we age, the proteins break down causing the lens to become cloudy. This is called a cataract.
-Usually cataracts mature bilaterally
3 main types of cataracts
- nuclear sclerotic – slow maturation, starts in 50s
- cortical – moderate maturation, causes myopic shift
- posterior subcapsular cataract (PSC) – fast maturation, common with steroid use or after vitrectomy
ddx of cataract should include
retinoblastoma due to absent of red reflex (White pupil)
cataract risk factors
aging, smoking cigarettes, steroid use, diabetes, sun exposure, congenital ToRCH syndrome (Toxoplasmosis, Rubella, CMV, HSV)
macular degeration is ..
MCC of permanent legal blindness and visual loss in the elderly
two types of macular degeneration
dry and wet
dry macular degeneration
(non-exudative) exam findings
drusen = round yellow spots (lumpy-bumpy) drusen are waste products from the RPE layer
Geographic atrophy, pigmentary changes
wet macular degeneration
(exudative)
Exam findings
Drusen, geographic atrophy, pigmentary changes + choriodal neovacularization
Choroidal neovascularization = new abnormal vessels that leak and bleed -> hemorrhaging, intraretinal fluid, subretinal fluid. These bad vessels secrete vascular endothelial growth factor (VEGF)
tx for wet and dry
Dry = amsler grid monitoring, eye vitamins such as PreserVision AREDS2 (zinc, A, C, E) -Wet = intravitreal injections of Anti-VEGF inhibitors, laser photocoagulation
s/s for macular degeneration
oBilateral loss or blurring of central vision oCentral Scotomas (black spots in central vision where atrophy or hemorrhaging is) oMetamorphopsia = straight lines appear bent (amsler grid)
