Congenital cranial dysinnervation disorder in a boy with congenital mirror movements.

"Mirror movements" are an axonal guidance disorder that consists of involuntary contralateral movements that mimic unilateral intentional ones, typically involving the fingers of the hand. They can be isolated or associated with conditions such as Klippel-Feil syndrome, Kallmann syndrome, or congenital hemiplegia. Isolated congenital mirror movements are sometimes caused by autosomal dominant mutation in the genes DCC or RAD51. At least 4 previously reported cases had strabismus, 3 with Moebius syndrome and 1 with Duane retraction syndrome. We report the case of a boy with an unusual incomitant strabismus consistent with orbital dysinnervation and suggest that for some patients with congenital mirror movements the neurological miswiring extends to the orbit, causing congenital cranial dysinnervation disorder.