Congenital fibrosis of the extraocular muscles.

Congential fibrosis of the extraocular muscles is characterized by the replacement of normal contractile muscle tissue by fibrous tissue or fibrous bands in varying degrees. The clinical entities which result from the fibrous replacement can be classified under the following headings: general fibrosis syndrome, congenital fibrosis of the inferior rectus muscle with blepharoptosis, strabismus fixus, vertical retraction syndrome and congential unilateral fibrosis, enophthalmos and blepharoptosis. Genetic factors may or may not be apparent. One pedigree with general fibrosis syndrome was traced through five generations. Light and electron microscopy demonstrated replacement of normal muscle by collagen and dense fibrous tissue with occasional areas of degenerated skeletal muscle. The surgical mangement attempts to achieve some functional readjustment of the ocular and lid position as well as the abnormal head posture. The surgical results were considered satisfactory when compared with the original position of the eyes and the backward head tilt.