It is extremely important for you to see an ophthalmologist very soon. This sounds like accommodative esotropia and it is a common cause of poor vision in one eye and the eye crossing and staying cross.
JCH MD
Dear Dr. Hagan. Thank you so much for a fast response. Just another question can this accommodative esotropia present itself so suddenl?y. One day she was totally fine (she is already almost 3 yrs and never had eye problems , even minimal) , and next day her eye is crossed? I took her to Opthalmology ER yesterday. They did a complete eye exam , dialation of the pupil and inside it seems to be all intact.Can this happen because of some kind of virus, or infection ? She is not febrile, and doesn't have any other symptoms. Can this happen due to trauma? She didn't fall, but was jumping on the bed , falling into the bed (sof surface) bacwards, just playing with her brother. Can activity like this somehow stretch the eye muscle? Sorry for all this questions , but I need to understand. Thank you again for being so kind and answering questions for parents like us.
Yes it can occur suddenly. If it was due to trauma or virus: 1. its there all the time (the eye crosses constantly). 2. The most common thing is called a 6th cranial nerve palsy.
HOWEVER when the eye is straight some times and not others then its likely the accommodative esotrophia which manifests itself when the child is trying to focus at something at near often the face of parents. It does come on suddenly and the most commage age of onset is ages 2 through 4.
These children are almost always farsighted (short eye) and the treatment is glasses which sometimes have to be bifocals. Often patching is required to give equal strength to each eye. Surgery is not a treatment for this type of esotropia. Some children do end up needing surgery for the crossing not corrected with glasses. HOWEVER the surgery does not get rid of the glasses.
Hopefully you are following up in an pediatric ophthalmology clinic.
JC MD