Eye Movements/Cataracts Flashcards
On exam, what would reveal late stages of Cataracts?
- No red light reflex present
- Lens is completely cloudy and cannot visualize retina
- Gradual, chronic, painless loss of vision
- Glare (especially at night)
Sxs of Cataracts
What are the 3 types of amblyopia?
- Strabismic
- Anisometropic or refractive
- Deprivational (congenital cataracts, ptosis, blocked visual axis)
What are the 3 main types of strabismus?
- Esotropia (crossing)
- Exotropia (wandering)
- Hypertropia (vertical misalignments)
Your role is to recognize misaalignment (strabismus) and refer to ophtho promptly to avoid risk of what developing?
Amblyopia
Cover/Uncover/Alternate cover testing:
“always deviated”
What is this called? What test should you do?
Tropia, use cover/uncover test
- Reduction in visual acuity of one or both eyes
- Caused by disuse or misuse during critical period of visual development
Amblyopia
Is strabismus intermittent or constant?
Either
- Explain surgical tx and prognosis of cataracts
- What is another temporary tx for cataracts?
- Cataract extraction surgery (lens removed and almost always replaced w/ intraocular lens)
- Excellent prognosis
- Prescription glasses (for temporary tx)
Cover/Uncover/Alternate cover testing
“sometimes deviated”
What is this? What test should you do?
Phoria, use cross cover (alternate) cover testing because it “breaks the fusion”
Disturbs binocular vision and increases risk of developing amblyopia
A complication of strabismus
What are the 3 less common forms of strabismus?
- Oblique muscle palsies
- Duane’s syndrome
- Brown syndrome
- family hx
- Low birth weight (prematurity)
- Neuro complications (CP)
- Poor vision
Risk factors for what condition?
Strabismus
What is the prevalence of strabismus?
Affects 4% of population. So about 1 child in each classroom.
- Congenital
- Intoxication
- Metabolic derangements
- Infections
- Tumors
Possible causes of nystagmus
- Opacity to natural lens of eye
- Often bilateral
- Severity varies
Cataracts
Does nystagmus cause decreases in visual acuity?
Sometimes, not always
- Decreased visual acuity
- Decreased color vision
- Opalescent changes to lens
- Abnormal or absent red light reflex
Signs of Cataracts
Rhythmic regular oscillation of eyes
Nystagmus
- Under what circumstances would you refer a person w/ cataracts to ophtho?
If lifestyle is affected
Alternating phases of slow drift in one direction w/ corrective quick movement in opposite direction.
Jerk nystagmus
- Tx depends on underlying cause (managed by ophtho/neuro
- Meds (baclofen, gabapentin)
- Botox
- Prism lenses
- Surgery (Kestenbaum muscle surgery)
- Or, no tx required
Tx for nystagmus
During what ages does visual development occur?
Birth –> 6/8 yrs old
