. Previous medical notes were reviewed and family history of strabismus noted. All affected individuals were invited for re-examination in cases where a positive family history of strabismus was reported; siblings, parents, and other family members, where appropriate, were invited to be examined for signs of Duane syndrome or infantile esotropia. 3) Cases of mosaic trisomy 8, which has been associated with Duane syndrome and infantile esotropia, were reviewed for signs of strabismus.