External Eye Part 1 Flashcards
What things can you look for during inspection?
sore, lesions, signs of inflammation, discoloration, and functional abnormalities.
Where can you look for abnormality during inspection?
Lids, lashes, Lacrimal apparatus, conjunctiva, sclera, cornea, iris, and pupils.
What is the baseline functional test? What is it?
Snellen or Sloan eye charts. Visual acuity at a distance.
Snellen has how much distance?
20 ft
Sloan chart needs how much distance?
10ft
Indirectly, the distal and near visual acuity tests (Snellen and Sloan) test what?
Anterior segments of eye Central vision optic nerve Visual centers of the brain (fovea centralis and macula lutea
Testing only the right side of the eye (distance) is called?
oculus dextra (OD)
Testing only the left side of the eye is called? (distance)
Oculus sinister (OS)
Testing both eyes together is called? (distance)
Oculus uterque (OU)
Term for eye having far sight but poor near sight.
hyperopia
Term for eye having near sight but poor far sight.
myopia
With age, >40, the lens loses its what?
Elasticity
The loss of elasticity in older years causes diminished near sight but continued far sight. This is called?
presbyopia
What is a common complaint in people over 50 (and in some young people)?
Vitreous floaters
What can vitreous floaters look like?
Cobwebs, spots, smudges
When are vitreous floaters concerning?
When they appear suddenly
How can you test near vision?
With a Rosenbaum chart or newprint
What distance is near vision tested?
14 inches
What is a blind spot called?
scotoma
What anatomy are the boundaries in testing the peripheral eye test?
eyebrow, cheek, nose, lateral face
Visual field deficits occur with what?
Abnormalities of the anterior segments of the eye
What can cause visual field deficits?
Scratching, scaring, edema of the cornea,
Cataracts on the lens
Pus or blood in the aqueous or vitreous fluid of eye,
Chronic glaucoma
Retinal detachments
Neural lesions along visual pathways
What causes progressive tunnel vision?
Chronic glaucoma
How can you test extraocular muscle strength and cranial nerves III, IV, VI?
Cardinal planes of gaze test
Which extraocular eye muscle is innervated by C.N. III?
Lavatory palpebrae superioris
Superior, inferior, and medial rectus
Which eye muscle is innervated by C.N. VI?
Lateral rectus
Which eye muscle is innervated by C.N. IV?
Superior oblique
What are ways to check symmetrical alignment of the eyes and therefore binocular vision?
Corneal light reflection and the cover-uncover test.
If there is a strabismus or a refractive difference between the eyes (during corneal light reflex or cover-uncover test) the brain will suppress the poorer image which leads to what?
amblyopia and monocular vision
Explain corneal light reflection.
A light shone at the eyes from a central position should cast a corneal reflection on the same point in each eye.
Asymmetrical reflections during the corneal light test implies what?
A congenital or muscle imbalance resulting in strabismus.
Explain the cover-uncover test.
Instruct patient to fix gaze on object. The doctor covers one eye with hand and uncovers (does on both eyes) looking for movement of that eye.
Movement in either eye during the cover-uncover test reveals what?
Acquired or congenital muscle imbalance resulting in strabismus.
When the eyes fail to work in a conjugate (coupled) fashion what will likely occur?
Monocular vision which affects depth perception.
