Exophoria is a form of heterophoria in which there is a tendency of the eyes to deviate outward. During examination, when the eyes are dissociated, the visual axes will appear to diverge away from one another.The axis deviation in exophoria is usually mild compared with that of exotropia. Cause
Exophoria can be caused by several factors, which include:

Refractive errors - distance and near deviation approximately equal. Divergence excess - exodeviation is more than 15 dioptres greater for distance than near deviation. Convergence insufficiency - near exodeviation greater than distance deviation.These can be due to nerve, muscle, or congenital problems, or due to mechanical anomalies. Unlike exotropia, fusion is possible in this condition, causing diplopia to be uncommon. Diagnosis
Prevalence
Exophoria is particularly common in infancy and childhood, and increases with age. References


== External links ==
This increase is due in part to a rise in the numbers of older mothers and of multiple births, where preeclampsia occurs more frequently. For example, in 1998 birth rates among women ages 30 to 44 and the number of births to women ages 45 and older were at the highest levels in three decades, according to the National Center for Health Statistics. Furthermore, between 1980 and 1998, rates of twin births increased about 50 percent overall and 1,000 percent among women ages 45 to 49; rates of triplet and other higher-order multiple births jumped more than 400 percent overall, and 1,000 percent among women in their 40s. == References ==