Fully accommodative esotropia
 
 

A patient with a right accommodative esotropia which only becomes manifested when looking  at a fixating object close-up   A patient with accommodative esotropia corrected with plus lenses   Left esotropia correctable with plus lenses.

The most common instruction is ' Please perform cover/uncover test on this patient'. The patient may or may not  be wearing their glasses. Ask the patient if he/she wears any glasses because you need to perform the test with  and without glasses. The patient wears hypermetropic glasses (if this is of the refractive type; in non-refractive type the patient may be  wearing bifocal) .  With the glasses on, the corneal reflexes are central in both eyes and the cover/uncover tests were orthophoric for near and distance (in partially accommodative esotropia there may be  esotropia on near fixation but its magnitude  is less compared to without glasses). With the glasses off, there is an esotropia (which may only be present with near fixation). The esotropia is increased  on near fixation (due to increased accommodation) but is less or absent with distant fixation. The ocular motility is otherwise normal.

Questions:

1. Do patients with accommodative esotropia always have significant hypermetropia?

answer
No, this is because accommodative esotropia may be refractive or non-refractive.
In refractive type, the patients have significant hypermetropia resulting in excessive accommodative convergence and therefore esotropia.
In the non-refractive type, the hypermetropia is usually normal for the patients' age but there is a high accommodative convergence to accommodation (AC:A) ratio. As a result, there is excessive convergence on attempted convergence leading to esotropia..

2. How can miotic be useful in treating accommodative esotropia?

answer
Miotic is useful in increasing the patients' accommodation and therefore reduces the accommodative convergence. However, its effect is less predictable than glasses and there are complications such as iris cyst, retinal detachment, cataracts. In addition, there is risk of repertory arrest during general anaesthesia if succinylcholine is employed.
.

3. Is surgery useful for accommodative esotropia?

answer
This will depend if the problem is refractive or non-refractive. If the problem is fully refractive, surgery should be avoided as correction of the eye can cause exotropia when the hypermetropia is corrected with glasses. In non-refractive surgery where there is a high AC:A ratio, surgery can be performed to correct the esotropia at near and permanently correct the AC:A ratio.
.

Return to the main page