Outcomes of strabismus surgery in genetically confirmed congenital fibrosis of the extraocular muscles

Congenital Fibrosis of Extraocular Muscles: A Retrospective Study of 76 Patients

Background Congenital fibrosis of the extraocular muscles (CFEOM) is a non-progressive sporadic or familial disease characterized by abnormal innervation of the extraocular muscles. This study aims to evaluate the types of diseases, management steps, and surgical outcomes. Methodology A total of 76 patients diagnosed with CFEOM between 2000 and 2022 were evaluated retrospectively. Patients were divided into CFEOM 1, 2, or 3 based on clinical findings. Preoperative and postoperative ocular deviations, as well as abnormal head positions (AHPs), of the patients were evaluated. Excellent outcomes for the head position were defined as less than 5°, good as less than 10°, and poor as greater than 10°. Excellent alignment for strabismus was considered to be less than 10 prism diopters (PD), good as less than 20 PD, and poor as greater than 20 PD. Results The average age at the first surgery in our clinic was 11.6 (1-51) years. The mean follow-up was 28.6 ± 7.4 months (range = 4-56 months). Type 1 disease was detected in 48 (63.2%) patients, type 2 disease in eight (10.5%), and type 3 disease in 20 (26.3%) patients. Of the 49 patients with AHP, 20 achieved excellent outcomes, 17 had good outcomes, and the remaining had poor outcomes. Ocular alignment in the primary position following the latest surgery was excellent in 30 patients, good in 26 patients, and poor in 20 patients. Conclusions No single best surgical method can be universally applied to every patient diagnosed with CFEOM. Patients must be evaluated individually and carefully, and the appropriate surgical procedure must be chosen. In this way, satisfactory gaze alignment and improvement of the AHP can be achieved.

Congenital Fibrosis of the Extraocular Muscles: An Overview from Genetics to Management

Congenital fibrosis of the extraocular muscles (CFEOM) is a genetic disorder belonging to the congenital cranial dysinnervation disorders and is characterized by nonprogressive restrictive ophthalmoplegia. It is phenotypically and genotypically heterogeneous. At least seven causative genes and one locus are responsible for the five subtypes, named CFEOM-1 to CFEOM-5. This review summarizes the currently available molecular genetic findings and genotype–phenotype correlations, as well as the advances in the management of CFEOM. We propose that the classification of the disorder could be optimized to provide better guidance for clinical interventions. Finally, we discuss the future of genetic-diagnosis-directed studies to better understand such axon guidance disorders.

Imaging of congenital cranial dysinnervation disorders: What radiologist wants to know?

We aim to review the imaging features of congenital cranial dysinnervation disorders. Characteristic imaging findings can define subtypes of these disorders through assessment of cranial nerves, extraocular muscles, orbital, and brain abnormalities. Duane retraction syndrome shows absent or hypoplasic 6th cranial nerve and preserved extraocular muscles (EOM). Mobius syndrome shows absent 7th and 6th cranial nerves, absence of facial colliculus, flattening of the dorsal aspect of the pons, hypoplasia of the pons and medulla, and flattening of the 4th ventricular floor. Congenital fibrosis of the extraocular muscles reveals unilateral or bilateral hypoplasia or aplasia of the 3rd cranial nerve, atrophy of superior rectus and levator palpebrae superioris muscles, and atrophy of the brainstem and cerebellar hemispheres. Horizontal gaze palsy and progressive scoliosis show characteristic split pons sign, butterfly medulla, absent facial colliculi, and spinal scoliosis. HOXA1 Mutations show a bilateral absence of 6th cranial nerves with the underdeveloped inner ear. Pontine Cap Tegmental Dysplasia shows ventral pontine hypoplasia, dorsal tegmental projection into the 4th ventricle, and variable cranial nerve deficits.