Refractive errors, Eye disorders not associated with systemic disorders Flashcards
What is the eye condition called when the patient has distorted vision caused by a variation in refractive power along different meridians of the eye?
Astigmatism
What astigmatism is the result of an irregularly shaped lens
Lenticular astigmatism
What astigmatism usually is caused by an irregularly shaped cornea?
Corneal astigmatism
What astigmatism has varying refractive powers in different meridians that can be reduced to 2 principle meridians at 90 degrees to each other?
Regular astigmatism
Which Regular astigmatism is when the vertical meridian has the greater curvature; most common in young Pts since most cases are caused by the shape of the cornea?
Astigmatism “with the rule”
Which Regular astigmatism is when the horizontal meridian has the greater curvature; more common in older pt as the cornea starts to flatten
Astigmatism “against the rule”
What astigmatism is due to uneven buldges of keratoconus, corneal scarring, lens irregularities, and pressure on the cornea from small tumors of the eyelids?
Irregular astigmatism
What type of astigmatism is a concave cylinder used for?
Myopic astigmatism
What type of astigmatism is a convex cylinder used for?
Hyperopic astigmatism
What is defined as incomplete visual development?
Ambylopia
What is defined as misalignment of the eyes resulting in two separate images appearing on the two retinas?
Strabismus
What is the most common strabismus of childhood?
Esotropia (congenital)
How do you differentiate between congenital esotropia and bilateral VI nn palsy?
See if eye laterally deviates, if it does, it is esotropia. If it doesn’t then it is bilateral VI nn palsy
What condition is known where refractive states
of the two eyes differs; one eye may focus a clear image on the retina without accomodation while the contralateral image is blurred leading to a unilateral amblyopia?
Anisometropia
T/F: Children may squint with only the affected eye with anisometropia
True
