Ambylopia Flashcards
What is amblyopia?
Amblyopia is a unilateral or bilateral decrease in best corrected visual acuity caused by form vision deprivation or abnormal binocular interaction without any pathology of the eye or visual pathway.
What is the typical cause of amblyopia?
Amblyopia is caused by form vision deprivation or abnormal binocular interaction.
During what critical period can amblyopia develop?
The critical period for amblyopia development is up to 8 years of age.
Name three amblyogenic factors.
Amblyogenic factors include absent/reduced image (e.g. cataract), image blurring from refractive error, and abnormal binocular interaction (e.g. strabismus).
What is strabismic amblyopia?
Strabismic amblyopia results from abnormal binocular interaction where the deviating eye experiences continued monocular suppression.
What is stimulus deprivation amblyopia?
Stimulus deprivation amblyopia is caused by vision deprivation, often due to media opacities like cataract or ptosis, and may be unilateral or bilateral.
What is anisometropic amblyopia?
Anisometropic amblyopia is caused by a difference in refractive error between the eyes, with as little as a 1 dioptre spherical (DS) difference resulting in blurred vision in one eye.
What refractive condition typically leads to bilateral ametropic amblyopia?
Bilateral ametropic amblyopia usually results from high symmetrical refractive errors, often hypermetropia.
What is meridional amblyopia?
Meridional amblyopia results from image blur in one meridian, typically due to uncorrected astigmatism greater than 1 dioptre.
What is an indicative sign of amblyopia in terms of Snellen visual acuity?
A difference of two or more Snellen lines in best corrected visual acuity without an organic cause is indicative of amblyopia.
What is the crowding phenomenon?
The crowding phenomenon refers to the exaggerated difficulty in recognizing objects or letters when they are close together.
What are two common treatments for amblyopia?
Treatments include occlusion of the better eye or penalization of the better eye by atropinization in mild amblyopia (6/24 or better).
