Sensory deprivation of a number of origins can cause an esotropia or exotropia. Causes may include congenital cataract, ptosis, retinoblastoma, colomboma- see below.

Congenital colomboma - defects of fusion of the optic cups is a rare cause of squint,. Note how the iris is incompletely formed giving a "keyhole" appearance	Congenital cataract - note the opacities in the lens medium shown up by the red reflex.
The left ptosis in this boy has caused a left esotropia	Retinoblastoma has caused an esotropia. There is gross bilateral ocular involvement