Congenital orbital fibrosis associated with fibrosis of extraocular muscle.

Congenital orbital fibrosis is a non-familial, unilateral, distinct clinical entity, characterised by the presence of a diffusely infiltrating orbital mass and is extremely a rare disease. Congenital orbital fibrosis with combined fibrosis of extraocular muscles have not been reported previously. We treated an 8-year-old boy with the presence of a diffusely infiltrating orbital mass and fibrosis of extraocular muscles with secondary involvement of extraocular muscles. Clinical examination revealed left exotropia, hypotropia and fibrosis of extraocular muscle, an irregular, retrobulbar mass located within the orbit, incorporating the optic nerve, medial, superior, inferior and lateral rectus muscle. The CT, MRI and light microscopic studies confirmed the diagnosis. We performed exploration of the orbit, release and biopsy of scar tissue and strabismus surgery. Unlike other reported cases, our case was a progressive congenital disorder with combined fibrosis of extraocular muscle.