exam 1 - eyes Flashcards
ophthalmic exam
-Should be a part of every well-child assessment
-Poor vision, misalignment of eyes, failed vision screening, eyelid malposition, abnormal pupil reactivity/shape, asymmetric/abnormal red reflex > ophthalmology referral
-Birth – 3 years
-History, vision assessment, inspection of eyelids/eyes, pupil examination, ocular motility, red reflex check; instrument-based screening may be attempted
-Children > 3 years
-Same as above plus visual acuity testing with eye charts and/or instrument-based screening
visual acuity (VA)
-Sleeping newborn: Presence of lid squeezing to bright light
-6 weeks of age: Eye-to-eye contact with slow, following movements
-3 months of age: Fixing/following movements with objects at distance (2-3 feet)
-6 months of age: Interest in movement across the room
-> 3 years: Eye charts
-Both eyes, then monocularly
-Passing = correctly answering majority of optotypes present on “critical line”
-Versus “threshold testing”
-Instrument-based screening: (dont need to know)
-Photo screeners - Screens for amblyogenic factors (strabismus, media opacities, eyelid ptosis, and refractive errors)
-Autorefractors- Above screening plus identification of refractive errors
red reflex test
-Ophthalmoscope at arm’s length from child with child looking straight at light
-Reflex should be light-orange/yellow in color
external exam
Penlight/blue light, eyelid eversion, fluorescein staining
pupils
Evaluated for reaction to light, regularity of shape, equality of size, presence of afferent pupillary defect
alignment/motility
-Evaluated in 6 cardinal positions of gaze
-Alignment:
-Observation (educated guess) < corneal light reflex < cover testing
-Corneal light reflex: Shine penlight and check where light reflects off each cornea
-know which defect causes medial and lateral displacement
-Cover test: Child focuses on target, each eye alternatively covered
-Shift in an eye’s alignment as it assumes fixation on target is possible indication of misalignment
amblyopia
-Unilateral or bilateral reduction in VA resulting from abnormal or inadequate stimulation of the visual system during the critical early period of visual development (prior to 8 years of age)
-Unilateral: MC causes are strabismus (misalignment of eyes) and anisometropia (difference in refractive error between two eyes)
-Bilateral: MC from high refractive errors (high hyperopia, myopia, or astigmatism)
-May have decreased contrast sensitivity, stereoacuity (3D vision), and fixation stability
-Screening with VA in each eye: Difference of two lines or more on an acuity chart between two eyes
-Pre-verbal screening: Strabismus, media opacities, unequal red reflexes, and/or family history
amblyopia tx
-Continued until amblyopia resolves (at least until 8-9 years of age)
-Eradication of refractive errors (glasses), cataracts/opacities
-If ineffective x 3-4 months:
-Increase stimulation of the amblyopic eye by part-time occlusion (patching) of sound eye
-Or fogging sound eye with cycloplegic drops, lenses, and filters
-patch the good eye to make the other eye work harder
strabismus: esotropia (cross eye)
-Deviation of eyes toward the nose (may involve 1 or both eyes)
-May be primary infantile (prior to 1 year), acquired (2-5 years), associated with syndrome, sign of CNS disease (> 5 years)
-Corneal light reflex – not centered in one or both eyes
-Restricted eye movements in certain positions of gaze
-Face turned towards affected eye to maintain binocularity (away from paretic muscle)
-Cover testing – Refixation movements laterally
-Complications: Amblyopia and poor stereoacuity/depth perception
-Treatment:
-Primary esotropia: Surgical correction between 6 months and 2 years
-Acquired/accommodative esotropia: Glasses with or without bifocals
-Neurologic causes: Specialist evaluation
strabismus: exotropia (wall eyed)
-Deviation of eyes toward the ears
-Begins intermittently and occurs after 2 years of age
-All children with constant, congenital exotropia require CNS imaging
-Corneal light reflex – displaced nasally in deviated eye
-Cover testing – Refixation movements nasally
Complications: Amblyopia < poor stereoacuity/depth perception
-Treatment:
-Observation, glasses, surgery
