aetiology
Last reviewed 01/2018
Causes include:
- strabismus - normal acuity develops in the eye used habitually for fixation, amblyopia in the non-preferred eye. This is most common in esotropia and rare in exotropia and hypertropia. It does not usually occur if there is spontaneous alternation of fixation.
- anisometropia; the eye with the greater refractive error is at risk of amblyopia.
- combined strabismic and refractive
- less commonly
- ametropia- if refractive error is large and symmetrical, may cause bilateral amblyopia
- stimulus deprivation(rare) - amblyopia results from interruption of the formation of an image on the retina:
- unilateral
- monocular cataract
- ptosis
- hyphaema
- opaque cornea
- cloudy vitreous
- iatrogenic - prolonged patching or prolonged atropine eyedrops
- bilateral
- nystagmus
- cataract
Reference:
- (1) Jefferis JM, Connor AJ, Clarke MP. Amblyopia. BMJ. 2015;351:h5811
- (2) Bradfield YS. Identification and treatment of amblyopia. Am Fam Physician. 2013;87(5):348-52.