Flashcards in Pathophysiology Deck (36)
What can be done to alleviate dry eyes?
plug in punctum, tears stay in eye longer, alleviate sx
What side of the eye is the worst to get a laceration on? Why?
medial side, because of superior and inferior canaliculi
can cut through and ruin drainage system
What does "injection" mean?
term used to describe the fine blood vessels that cause the conjunctiva to look pink or red
What are the common causes of intracranial hypertension?
-venous sinus thrombosis
What is the most commonly affected muscle in graves ophthalmopathy and what does this affect?
results in vertical diplopia
What are the s and s of graves ophthalmopathy?
excessive tearing, conjunctivitis, eye or rtetroorbital pain
blurred vision, dipolplia
What is the pathogenesis of Graves ophthalmopathy?
T lymphocytes activated, results in inflammation and infiltration of the orbital connective tissue
inflammation results in more deposits of collage and glycosaminoglycans in the muscles, which then swell and grow and push eye out of socket
What are the complications of graves ophthopathy?
-dry eyes, corneal ulcerations (from proptosis)
-EOM (diplopia, inability to look up, inability to converge)
what is proptosis?
forward perfusion of the globe with respect to the orbit
What is the treatment for Graves opthalmopathy?
-treat underlying hyperthyroidism
-mild sx (dark glasses, eye drops, raise head of bed)
-severe sx (glucocorticoids and if vision is threatened, radiation and then surgery)
What happens with Myasthenia Gravis (MG)?
ACh is gone, muscles don't contract, get weakness, resulting in ptosis and binocular diplopia
can treat with anti cholinesterase meds (increasing the ACh available so there are less symptoms)
chronic or rapid immunomodulating to treat the AI
surgical (can remove thymus)
What are the red flags in ophthalmology?
-reduction of visual acuity
-severe deep pain (not irritation)
-severe foreign body sensation the prevents pt from keeping eye open
-severe headache with nausea
What is a ciliary flush?
patter of injection in which redness is MOST PRONOUNCED in a ring at the limbus (the limbus is the transition zone between the cornea and the sclera)
What is a subconjunctival hemorrhage?
signs, symptoms and dx, tx
blood vessel burst from conjunctiva
signs: red in eye
dx: no photophobia, no foreign body sensation, no discharge, no change in visual acuity
tx: none, will heal in 1-2 weeks
What is keratoconus?
signs, sx, dx, tx
a degenerative disorder that causes the cornea to thin and change shape into more cone shape rather than curve
signs and sx: distortion of vision, photophobia, trouble reading, driving
tx: corrective lenses, and in some cases, surgery (corneal transplant, etc)
What are the four types of corneal abraisoins?
-foreign body related
Corneal abraision. traumatic causes and pathophys
mechanical trauma to eye which results in defect in epithelial surface
caused by: fingernails, paws, paper, leaves, tools, branches (different than foreign body like wood or glass)
corneal abrasions, foreign body related causes and pathophys
pathophys: defects in corneal epithelium that are left in eye after removal or dislodging of a corneal foreign body
causes: wood, rust, glass, plastic, fiberglass
corneal abrasions, contact lens related causes and pathophys
patho: defects in corneal epithelium that are left behind after removal of over-worn contacts, improperly fitting, or improperly cleaned contact lens
caused by:physical contact with lens, debris on or under lens, poor handling of lens during insertion or removal
corneal abrasions, spontaneous related causes and pathophys
**usually in AI diseases, cornea is thinner so get more abraisions
patho: no immediate antecedent injury or foreign body
characterized by a disturbance at the level of the corneal epithelial basement membrane, resulting in defective adhesions and recurrent breakdowns of the epithelium
Why do patients get photophobia?
b/c contraction of the ciliary muscle is painful-- remember that ciliary muscle is continuous with the iris, and the iris contracts (the circular muscles) with light
What is the clinical presentation of someone with a corneal abrasion?
-foreign body sensation with inability to open eye
-too uncomfortable to work, drive, read
A patient presents with a eye pain and a foreign body sensation, also photophobia. You presume a corneal abrasion. But what is your NEXT step?
ruling out penetrating trauma
rule out infectious infiltrate
In a history with a patient who has sx of corneal abrasion, you ask about traumatic abrasion (was it a leaf, did kid throw a book, did you hit a branch, dog paw, etc) or if the patient is a contact lens wearer, or if it was a foreign body incident. If it was a foreign body incident, what is considered?
Penetrating trauma until proven otherwise
foreign body. eye exam. what do you look for, what do you worry about (pupil, and anterior chamber)
worry about pupil dilation (injury to circular muscle) call ophtho
pupil constriction is ok, eye is reacting from abrasion (miosis)
is there hyphema or hypopyon? if yes, call ophtho
eye exam with corneal abrasion. what will you see and do?
visual acuity: may be normal if abrasion is away from visual axis, and abnormal if abrasion is on visual axis (just keep the abnormal one in mind to know that pt may have visual acuity change but doesnt mean has deeper eye problem)
-injection if longer than 2 hours
-NO corneal opacity
-make sure perform funduscopic exam
** IF YOU CANNOT RULE OUT PENETRATING TRAUMA, DC EXAM AND CALL OPHTHALMOLOGIST
When do you do a fluroscein stain with eye exam?
AFTER penlight and funuscopic exam IF:
corneal abrasion is suspected AND there are lack of signs of other disorders
(make sure inspect well and use magnifying glass and woods lamp)
What treatment do you use for traumatic and foreign body abrasions? IN THE ABSENCE OF CONTACT LENS TRAUMA?
topical abx because ointment is better than drops b/c lubricates the eye
erythromycin and sulfacetamide
-can also give cyclopeligic agents (help with pupil construction to light which helps with pain)
-systemic therapy like lortab (opiod) for pain
CI: steroids and aminoglycocides
aminoglycosides are toxic to epithelium
steroids slow healing
What are NOs with traumatic and foreign body abrasions as far as healing?
steroids, aminoglycosides, patches
NO prescription topical anesthetics!
What are the warning signs of an ulcer and not an abrasion?
-purulent or watery discharge
-corneal appearance that is variable and could be cloudy (NOT CLEAR)
What is the cause of a dendritic, branching ulcer? What does it lead to?
-herpes simplex keratitis
-DOES NOT lead to corneal scarring, but will LEAD TO BLINDNESS
With a fungal infection, when does it tend to occur and where do you normally see the infection?
-occurs in outside workers especially agriculture, and contact lens wearers
-see more stromal accesses, and little epithelial loss
What type of corrected lens/contacts do you use with pt who has myopia?
glasses: divergent, concave
What type of corrective lens/contacts do you use with a pt who has hyperopia?
glasses: convergent, convex
What kind of conjunctivitis is most common in kids, adults, neonates?