Learning IV Flashcards
What is amblyopia?
Amblyopia (‘lazy eye’) is characterised by poor vision in one eye caused by disruption to normal visual input during the critical period. It is the most common cause of monocular vision loss in children.
1/3 have strabisimus, 1/3 have anisometropia & 1/3 have a mix of the two.
2-4% of the population affected.
What is the main difference in amblyopic vision compared to normal vision?
In normal vision, object of interest is imaged on corresponding points on the two retinas and fused for binocular vision, whereas in amblyopic vision, suppression prevents visual signals from deviating eye reaching conscious awareness.
Outline the history of treatment for amblyopia?
de Buffon (1743) introduced occlusion therapy for treatment. It has remained relatively unchanged since and is the frontline treatment for amblyopia.
Limitations: distressing treatment for children, can adversely affect social and educational development.
Can lead to binocular vision problems e.g. reduced stereopsis. Also issues with compliance in the treatment, and the gains are not stable - only about 50% report an improvement.
Can refractive correction be used as an alternative treatment for amblyopia?
RC can cure amblyopia in children if the acuity deficit isn’t too pronounced, and if administered over a 12-16 week period. Occlusion therapy should only be used after this has plateaued.
Does occlusion therapy have to be administered part-time or full-time?
Studies have shown that part-time occlusion therapy can have the same benefits as full-time therapy, with a recorded improvement of 1 line on a logMAR letter chart.
