Congenital fibrosis of the extraocular muscles

Background: Congenital fibrosis of the extraocular muscles (CFEOM) describes a group of rare congenital eye movement disorders that result from the dysfunction of all or part of the oculomotor (CN 3) and the trochlear (CN 4) nerves, and/or the muscles these nerves innervate.

Aim: To describe the clinical and neuro-radiological findings in three patients with CFEOM and review literature with respect to clinical features, genetics and management of this condition.

Materials and methods: A retrospective chart review was performed of three Omani patients who had been diagnosed with CFEOM in our institution. All patients had undergone standardized orthoptic and ocular evaluations and magnetic resonance imaging (MRI) of the orbits and brain.

Results: The three patients (age range nine months - 10 years) presented a history of congenital strabismus. All patients had severe bilateral ptosis and mild to moderate visual impairment secondary to the ptosis and astigmatism. Two of three patients demonstrated a positive jaw-winking phenomenon. A moderate to large angle exotropia with varying amount of hypotropia and limitations of almost all the extra ocular muscles was noted. Patient 3 was also developmentally delayed. MRI brain and orbit showed abnormalities of the extraocular muscles in two patients and brain malformation in one patient.

Conclusions: CFEOM is a rare, congenital, and non-progressive disorder with multiple extra ocular muscle restrictions. CFEOM can be associated with neuro-radiological abnormalities; its diagnosis and classification is defined by clinical characteristics and genetics. Options for treatment are limited and difficult.

CFEOM; ophthalmoplegia; ptosis; restrictive strabismus.