Abraham Lincoln experienced intermittent left hypertropia during his adult life. Several photographs show him with a right head tilt, making it likely that he had an underaction of the left superior oblique muscle. This was possibly an effect of his underdeveloped left orbit with its rounded upper rim, a manifestation of premature closure of his left coronal suture. This led to a unilateral plagiocephaly with marked facial asymmetry. His son Robert Todd Lincoln had an even more marked left hypertropia and also showed facial features of a unilateral synostotic coronal plagiocephaly.

Submitted by Ronald S. Fishman, from the Cogan Ophthalmic History Society.