Alternating ptosis associated with intermittent exotropia.

A unique case of alternating, poorly controlled, intermittent strabismus that improved after repair of bilateral, alternating congenital ptosis is described. A 7-year-old boy with bilateral, alternating congenital ptosis and poorly controlled, intermittent exotropia underwent bilateral frontalis suspensions. After surgery, the patient demonstrated improved control of his exotropia. We conclude that an alternating ptosis may lead to sensory deprivation of the occluded eye and decreased fusion, causing an intermittent strabismus to be poorly controlled. Repair of the ptosis to a sufficient eyelid height bilaterally may improve control of the strabismus, obviating strabismus surgery.