Strabismus Flashcards
Name all types of exotropia under the consecutive exotropia.
Spontaneous & postoperative consecutive.
What does concomitant mean?
The angle of the strabismus is the same with all positions of gaze of each eye fixating.
What are the sub-classifications of non-accommodative esotropia? Name all types of esotropia under the sub-classifications.
Constant & intermittent.
Constant: infantile, acquired non-accommodative, nystagmus block, microesotropia, associated with myopia.
Intermittent: near, distance, cyclical.
What type of uncorrected refractive errors cause strabismus?
Myopia, hypermetropia, anisometropia, astigmatism.
Name all types of esophoria.
- Convergence excess
- Divergence weakness
- Non-specific
What are the classifications of esotropia?
first two classifications
Accommodative & non-accomodative.
What does incomitant mean?
The angle of strabismus is different with different positions of gaze of each eye fixating.
What type of strabismus would hypermetropia cause and why?
Esotropia because there is an over accommodation & convergence.
What is the aetiology of strabismus?
There are 9 causes.
- Embryonic factors
- Innervation/mechanical factors
- Fusion defects due to sensory deficits
- Neurodevelopmental
- Premature birth
- Accommodation/convergence issues
- Refractive error
- Genetics
- Anatomical defects
What are two types of strabismus?
Concomitant & incomitant.
Name all types of exophoria.
- Convergence weakness
- Divergence excess
- Non-specific
What are the sub-classifications of accommodative esotropia? Name all types of esotropia under the sub-classifications.
Constant & intermittent.
Constant: partially accommodative.
Intermittent: fully accommodative, convergence excess.
What are the classifications for exotropia?
Primary & consecutive.
How will anisometropia & astigmatism cause strabismus?
Dissimilar images/poor images affect the fusion hence strabismus.
What are the sub-classifications of primary exotropia? Name all types of exotropia under the sub-classifications.
Constant & intermittent.
Constant: early onset, decompensated intermittent.
Intermittent: near, distance, non-specific.
What type of strabismus would myopia cause and why?
Exotropia because there is an under accommodation & convergence.
What is the definition of pseudo-strabismus?
The appearance of a strabismus even though the visual axes are aligned under binocular viewing conditions.
What is the aetiology of pseudo-strabismus?
there are four points.
- lid anomalies
- ocular anomalies
- anomalies in relative position of orbits
- optical anomalies
What are the examples of lid anomalies?
- epicanthus
- blepharophimosis (BPES)
- abnormality of lid margin: ectropian & entropian
- abnormality of upper lid margin
- abnormality of lid position: ptosis & lid retraction
What are the examples of ocular anomalies?
- coloboma
- anisocoria
- enophthalmos
- exophthalmos
- corectopia
- heterochromia
- angle kappa
What are the examples of optical anomalies?
Big & small glasses.
What are the examples of anomalies of relative position of orbits?
- orbital asymmetry
- IPD
- epicanthus
- palpebral fissure
