corneal disorders Flashcards
transparent outermost layer of the eye that covers the pupil and iris and allows light to enter the eye
cornea
opacities of the lens – usually bilateral
cloudy
leading cause of blindness worldwide
cataracts
cataracts MC cause
age related
cataracts other causes
congenital (from intrauterine infections such as rubella) (errors of metabolism)
topical, systemic, or inhaled corticosteroid treatment
radiation exposure
cataracts risk factors
> 60 years of age
cigarette smoking
progressive blurring of vision
glare (especially in bright light or with night driving)
change of focusing (development of nearsightedness)
can be seen on exam with dilated pupil even when it is small
as it progresses the funds loses its reflex and pupil appears white
cataracts clinical findings
cataracts treatment
refer to ophthalmology (not emergent)
lens replacement*
scratch or injury to the surface of the cornea
corneal abrasion
corneal abrasion causes
trauma
foreign bodies
contact lens (over worn, improperly fitting, improperly cleaned)
corneal abrasion presentation
severe pain
photophobia
foreign body sensation
what to do first on a corneal abrasion exam
check visual acuity before tetracaine or fluorescein
corneal abrasion: patient will be in severe pain. what to use to anesthetize
tetracaine
what exam to do with corneal abrasion
lid inversion with q tip to r/o foreign body
why should you be cautious with tetracaine
toxic to epithelium and can slow healing which increases risk of corneal infection and scarring
what exam to do with corneal abrasion if you are not certain
fluorescein stain
(defect will light up green)
corneal abrasion treatment
bacitracin- polymyxin/erythromycin ophthalmic ointment (antibiotic and lubricant)
oral NSAIDS/topical NSAIDS
corneal abrasion treatment for contact lenses (pseudomonas)
don’t wear contacts for 1 week
ciprofloxacin or other fluoroquinolone eye drops
what should you not use with corneal abrasion
antibiotic drops with steroids
reduce host resistance to superinfection and may make missed diagnosis of HSV, epithelial keratitis, or microbial keratitis worse
what should you not send the patient home with in corneal abrasion that they may ask for
tetracaine
causes delayed healing
treatment for large corneal abrasions > 50%
cycloplegic drops
(dilate eye to reduce pain)
patching
defect in the corneal epithelium
crater, open sore
corneal ulcer
corneal ulcer usually due to
infection
long term contact lens use
can be due to conditions that lead to persistent eye irritation
corneal ulcer delay/ failure to treat can lead to
scarring or intraocular infection
what can you expect to see with corneal ulcer
irregular border and hazy
pain
photophobia
tearing
reduced vision
corneal injection
may have discharge
corneal abnormality
corneal ulcer treatment
refer emergently to ophthalmology
most likely will have you initiate antibiotics with close follow up
what to do with foreign body on cornea
check vision *
remove with sterile wet cotton tipped applicator or with 25G needle
bacitracin-polymyxin/erythromycin opthalmic ointment
what to do if foreign body cornea cannot be removed or corneal infection is suspected
send to ophthalmology right away
foreign body intraocular usually affects those who
work with metal
high speed injury
if no corneal FB is seen but there appears to be a wound
if there is visual loss or media opacity
deeper than cornea
foreign body intraocular
what to do with foreign body intraocular
emergent referral to ophthalmology
keratitis bacterial MC pathogens
staphylococci
streptococci
pseudomonas aeruginosa
moraxella species
infection of the cornea
corneal opacity or infiltrate with red eye, photophobia, and foreign body sensation
agressive
often have purulent discharge
keratitis bacterial
keratitis bacterial affects who
usually contact lens wearers
overnight use
sometimes after trauma
how to make keratitis bacterial diagnosis
seeing the opacity (usually it is > 0.5 mm) with the other symptoms
- red eye
- photophobia
- foreign body sensation
hypopyon*
keratitis bacterial treatment
needs to see ophthalmology emergently
topical antibiotic usually under direction of ophthalmology, usually fluoroquinolone given hourly
what to avoid in keratitis bacterial
NO steroid drops
stop wearing contacts
herpes simplex (HSV)
red eye, photophobia, foreign body sensation, and watery discharge
primary infection may affect lid, conjunctiva, and cornea
dendritic lesion is characteristic manifestation (seen with fluorescein)
keratitis viral
keratitis viral treatment
self limited
antivirals and topical corticosteroids (to reduce duration of treatment)
refer to ophthalmologist
the virus in keratitis viral recurrence can colonize the __________ and recur
trigeminal ganglion
- fever
- exposure to sunlight
- immunodeficiency
keratitis viral recurrence can be stroll risk for
corneal scarring
occurs after corneal injury involving plant material or in an agricultural setting
occurs in eyes with chronic ocular surface disease and in contact lens wearers
corneal infiltrate may have feathery edges and multiple “satellite” lesions
keratitis fungal
does pinguecula get larger
rarely, but may get pingueculitis
keratitis viral diagnosis often ________ and treatment _________
delayed, difficult
degenerative and benign lesion
yellow nodule on the conjunctiva, usually on nasal side (contain fat, protein, calcium)
common over the age of 35
usually bilateral
pinguecula
pinguecula treatment
no treatment is required but artificial tears may help
topical anti-inflammatories may be needed
fleshy triangular conjunctival tissue that grows on to the cornea, the nasal side
usually bilateral
pterygium
what is pterygium associated with
long term exposure to wind, sun, sand, dust
what do you have to watch for with pterygium
may get larger and/or inflamed
pterygium treatment
artificial tears or topical NSAIDS
sometimes they are excised (growth that threatens vision, astigmatism, severe irritation)
