PD - Ophthalmology Exam Flashcards
Myopia
Near-sighted
eye too long, image projected in front of retina
Hyperopia
Far-sighted
eye too short, image projected behind retina
Astigmatism
an eye with a cornea with differing refractive powers in one meridian compared to another
Accommodation
ability of the ciliary muscle to contract causes a change in the shape and power of the lens, allowing the eye to focus at near.
slowly lost thru life.
Miosis
pupillary constriction
Mydriasis
pupillary dilation
Finding the optic disc
At an angle slightly lateral to pt’s line of vision…
Focus on red reflex back to the retina within the pupil using ophthalmoscope. (red-orange reflection from the pupil)
Find a retinal vessel, track back to optic disc. (if vessel is getting smaller, may be leading away from disc)
Steps of the Eye Examination
- Test Visual Acuity
- Test Pupillary Response (pupillary light reflexes)
- Inspect lids
- Inspect the Conjunctiva and Sclera
- Test Extra-Ocular Movement (EOM) and ocular alignment
- Test Visual Fields
- Inspect the Cornea, Iris, and Anterior Chamber
- Check Red Reflex
- Perform Retinal Examination
- Perform Tonometry
Visual acuity test
Distance and near vision (with corrective lenses, if patient uses them)
- Record each eye individually
- Record circumstance (i.e., w/ contact lens, wall chart at 20 feet,)
or Count Fingers at x feet, Hand Motions at x feet, Light Perception (if vision very poor)
Common causes of decreased visual acuity
- Refractive disorder
- Amblyopia: poor vision in an otherwise normal eye, sometimes caused by strabismus
- Corneal abrasion or infection
- Age-related macular degeneration or cataract
- Optic neuritis or ischemic optic neuropathy
anisocoria
difference in pupil diameter not greater than 1mm
3% of population
pathologic = indicates disease of the iris, sympathetic nerves (efferent loop,) or CN III
Horner Syndrome
Ipsilateral Ptosis, Miosis, and Anhydrosis
Direct Pupillary Response
Test miosis with light shined in one eye. (CN II aff, CN III eff)
Consensual Pupillary Response
Opposite pupil should constrict with light in one eye
Swinging Flashlight Test
Tests for relative AFFERENT pupillary defect (Marcus Gunn pupil) – decreased function of Cranial Nerve II (or retina.)
Shine light in one eye, then shift to other eye (pupils should remain equally constricted)
(if they instead dilate slightly, then there is an afferent pupillary defect)
-affected eye still senses the light and produces pupillary sphincter constriction to some degree, but is reduced.
Accommodation Reflex
Ask patient to focus on a distant object (finger) then move it toward their nose.
-Eyes should converge and slightly constrict.
(ciliary muscle also contracts, lens –> convex, but this is not usually visible w/o equipment.)
Why perform the swinging flashlight test?
A relative afferent papillary defect is 92-98% sensitive in detecting asymmetrical optic nerve disease (optic neuritis, etc.)
Anisocoria is absent in disease of …
CN II (afferent loop) or retina
Inspecting lids/surrounding tissues
- Assess for masses, edema, erythema, and asymmetry
- Inspect lid margins for debris, erythema, discharge
- Note where upper eyelids crosses the cornea/pupil
- Evert and inspect under upper eyelid
Proptosis
Grave’s orbital inflammation or tumor, orbital cellulitis, blunt injury
Ptosis
CN III palsy, Horner’s, myasthenia gravis, dermatochalasis
Swollen lids
chalazion, stye, dacryocystitis
Tearing
dacryocystitis, blepharitis, orbital inflammation, ocular foreign body, allergy
Discharge
allergic, bacterial, viral or chlamydial conjunctivitis, dacryocystitis, orbital inflammation
