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
conjunctive components (2)
Palpebral conjunctiva (inside of the lids)
Bulbar conjunctiva (covers the surface of the eye).
Should be smooth, pink, and moist, without discharge.
Superior Rectus (CN III)
elevation, (intorsion, adduction); upward gaze
Inferior Rectus (CN III)
depression, (extorsion, adduction); downward gaze
Lateral Rectus (CN VI)
abduction; lateral gaze
Medial Rectus (CN III)
adduction; medial gaze
Superior Oblique (CN IV)
Intorsion, depression, abduction; downward inward gaze
Inferior Oblique (CN III)
Extorsion, elevation, abduction; upward outward gaze
Ocular Alignment
Have patient look ahead and shine light at eyes.
Spot of light reflection should be symmetric.
If cover one eye and light reflex changes on the non-covered eye –> strabismus (lack of coordination between the eyes) w/ covered eye being dominant eye.
Confrontational Visual Fields
Close one of your eyes and tell pt to look at your open eye
have patient tell you when objects enter/exit their visual field (test by counting fingers in all 4 quadrants)
test sfor subtle, focal areas of vision loss (typically indicate more severe pathology)
Common causes of visual field abnormalities
- Tumors of optic chiasm
- CVA or tumor
- Retinal vascular occlusion
- Optic neuritis or ischemic optic neuropathy
- Glaucoma
- Retinal detachment
Areas of denuded corneal epithelium stain ______ after flourescein stain
bright green
Assessment of anterior chamber depth
Shine penlight on cornea from side.
Shadow of iris should not be greater than one-half of the iris on opposite side
Examining the optic disc
- Inspect margins
- Assess color
- Estimate cup area
- Look for vertical elongation of cup
- Look for notches in rim, asymmetry of rim contour
- Compare to opposite eye
Examining the retina
- Red spots: hemorrhages
- Dot, blot-shaped red spots: deeper intraretinal hemorrhages
- New vessels: fine, tortuous (diabetes)
- Soft white, feathery patches: cotton-wool spots (sign of retinal ischemia)
- Discrete yellow retinal spots: hard exudates, usually cholesterol deposits
assessing for retinal detachment, papilledema
Assessing IOP (performing tonometry) directly
palpate closed eyelid, the globe should be firm, but slightly giving. A hard globe indicates an elevated IOP.
Inspection of cornea and iris steps
- general inspection
- fluorescein stain
- anterior chamber depth
