Absence of multiple extraocular muscles in craniosynostosis

The absence of extraocular muscles, particularly the superior rectus1, 2 or superior oblique3, 4 has been recognized to cause strabismus among patients with craniosynostosis. Absence of multiple muscles is less common. In case 1 we note a patient with Pfieffer's syndrome and absent left superior rectus and inferior oblique, with the presence of only a vestigial left superior oblique and an underdeveloped and misinserted left inferior rectus. In case 2 we describe a patient with Apert's syndrome with bilateral absence of the superior rectus and superior oblique muscles. Unsuspected superior rectus absence led to a bilateral elevation deficit after inferior oblique weakening. Also, during the course of treatment, all 3 remaining recti muscles in 1 eye were disinserted. To our knowledge, this is the first report of absent extraocular muscles in Pfieffer's syndrome. Some evidence suggests that collateral anterior segment blood flow exists in cases of absent recti muscles. Further study is needed to determine whether all remaining muscles could be used for strabismus repair. Last, when patients with craniosynostosis require strabismus surgery, we feel that a limited exploration of all extraocular muscles should be carried out.