Handedness in strabismics. Etiological implications

The incidence of non right handedness was found to be significantly higher in a group of 228 strabismics when compared with a control group of neurologically normal non strabismic subjects. The difference was still present after elimination of strabismics with known neurological or general health problems, or who were born prematurely. The strabismics showed no inter group differences in handedness in relation to the type of retinal correspondence present or the ability to achieve normal or abnormal binocular single vision. Evidence is reviewed for the presence of a developmental defect leading to strabismus, and results of this survey support a previously proposed idea that a developmental defect leads to strabismus, the type of which reflects the severity of the defect (although external factors may also be an influence).