Pathologies of eyes and anatomy Flashcards
What are the 7 bones that support/stabilize and protect the eye?
- Frontal bone
- Ethmoid bone
- Lacrimal bone
- Maxilla
- Palatine bone
- Zygomatic bone
- Sphenoid bone
External anatomy for eyelids/eyelashes
- protection > skin > protect us from external foreign bodies
- moist> blink 5” > H20, oil
- exposure> light/heat
pupil is known as
the gateway of light
iris is known as
controlling the amount of light, controls constriction/dilation
cornea is known as
anterior protectionary piece, and the first contact of light
There are two types of photoreceptors
- cones (sharp, central, color vision)
- rods (night black/white, peripheral vision)
- these create the optic nerve
We have the ability to see due to the ____, which transfers visual information from the retina to the vision centers of the brain via electrical impulses
Optic nerve
Anterior cavity
- contains aqueous humor
- going to extend from the cornea, iris and the lens
Posterior cavity
- contains vitreous humor
Anterior chamber
going to extend from the cornea to the iris
Posterior chamber (creates the anterior cavity)
going to extend from the iris to the back of the lens
the conjuctiva is
thin covering of the eye and eyelids
6 muscles that drive the eye
- lateral rectus
- medial rectus
- superior rectus
- inferior rectus
- inferior oblique
- superior oblique
Lateral rectus is
move the eye laterally
medial rectus is
move eye medially
superior rectus is
move eye up
inferior rectus is
move eye down
inferior oblique is
move eye up & laterally
superior oblique is
move eye down & laterally
what are the 3 cranial nerves of the muscular anatomy of the eye?
- oculomotor
- medial, superior, inferior rectus & inferior oblique - trochlear
- superior oblique - abducens
- lateral rectus
What are the immediate referral when doing inspection of the eye?
Photophobia= tolerate light
Diplopia= double vision
Hyphema= blood in anterior chamber
ROM= limite
Abnormal= pupil Rxn
Inspection of the Periorbital area and globe
- Discoloration
- hematoma (skin surrounding eye swells easily “black eye” - Gross deformity
- lacerations
- gross bony deformity (step-off, piano key sign) - eyelids
- swelling, ecchymosis, laceration, stye - cornea
- cloudiness= intraocular pressure (immediate referral) hyphema
What is 20/20 vision
patient’s ability to read at 20ft what normal person could read at 20ft (emmertropia)
What is 20/40 vision
patient’s ability to read at 40ft what normal could read at 20
What is myopia
nearsightedness (light rays focused in front of retina)
What is hyperopia
farsightedness (light rays focused behind retina)
Conjunctivitis (infection)
Viral or bacterial infection= “pink eye” (viral is most common)
- Pain: mild discomfort, not really pain
- Vision: temporary mild blurring due to discharge
- Discharge: watery (viral), mucoid (bacterial)
- Pupil: not affected
- Cornea: clear
Treatment for conjuctivitis
-bacterial: antibiotic drops, (typically more pain), warm compress
- viral: warm or cold compress or artificial tears (found in pharmacies), optometrist may prescribe anti-inflammatory drops, antihistamine if viral
Stye pathology
acute, purulent infection of the oil glands of the eyelid or eyelash follicles due to clogging
Stye s/s
-redness, tenderness and pain
- irritated or “scratchy”
- common to have small, yellowish pus in the area (staph)
Treatment for stye
Application of warm compress or washcloth to affected area for 10-15 minutes, 4x/day to assist w/drainage
Subconjunctival hematoma etiology
trauma, bleeding disorder, high blood pressure, Vasalva maneuver (sneezing, coughing)
- pain: absent
- vision: not affected
- Discharge: absent
- Pupil: not affected
- Cornea: clear
Referral criteria for subconjunctival hematoma
pain, changes in vision (diplopia), altered pupil
Treatment for subconjuctival hematoma
artificial tears 4x daily to irrigate
Corneal injury or infection
- Abrasion: trauma from sport, removing contacts
- pain: moderate to severe (7-10 scale)
- vision: usually decreased
- Discharge: watery
- Pupil: not affected
- Cornea: divot, cloudy (fluorescence swab to detect)
Corneal Abrasion typical presentation (s/s)
- photophobia
- watering
- foreign body sensation
- gritty feeling
- pain
Corneal Abrasion management
- ophthalmologist Rx topical antibiotic and analgesic
- do not wear contacts
-eye patch PRN
Corneal laceration treatment
- cover w/gauze
- refer
- copious irrigation
Orbital “blowout” fracture
s/s: swelling, ecchymosis, diplopia (especially on upward gauze)
Orbital socket
with blunt trauma, maxillary bone fractures downward most often and orbital content herniate down into underlying maxillary sinus, creating a “blowout” fracture
Orbital socket s/s
enopthalmia, entrapment of inferior rectus muscle (prohibiting superior rectus from upward rotation)
Acute iritis pathology
inflammatory reaction in anterior chamber
Acute iritis etiology
typically blunt trauma, chemical burn, but also idiopathic
Acute iritis
-pain: moderate deep ache, pressure
- Vision: decreased
- discharge: absent
- Pupil: may be small and irregular, sluggish in reacting (may be photophobic)
- Cornea: clear or slightly cloudy
Acute iritis significance
may be due to ocular or systemic disorder (rheumatoid arthritis)
Acute iritis management
typically referral for corticosteroid eyedrops
Retinal detachment
- may cause “floaters”
(vitreous humor dislodges from retina) - refer to emergency dept for ophthal consult if patient photopsia: starts to see floaters, flashes of light and dark shadows
Hyphema
- accumulation of blood in the anterior part of the eye that may cover the iris and pupil
- usually result of ruptured iris root vessel
- ophthalmologist consult (eye shield)
Foreign body (benign)
- do not remove!
- copiously irrigate eye with clean, warm water to remove object and relieve symptoms
- reassure patient calmly
- apply loose bandage and cover object if small
-REFER
S/s of optic nerve damage
Blurred vision
- failure to code impulses for transmission to brain for interpretation
Abnormal peripheral vision
Interpretation problems
- altered information presented to brain
Decreased constriction (PEARL= oculomotor mostly; optic is afferent supply)
- Photophobia
Differential Dx for eyesight loss
Damage to one optic nerve
- between eye and chiasm
- optic nerves have not converged, so sight loss in only one eye
Damage at the optic chiasm
- located where two nerves meet, so loss occurs in peripheral vision (pt. can see straight ahead but not to side)
Damage closer to the brain
- between chiasm and brain
- part of visual field will be lost in both eyes
