What is Moebius Syndrome?
This rare condition was described by Von Graefe and Moebius in the 1880’s; since then, over 300 cases have been reported in the medical literature. It is a developmental facial paralysis (DFP) because the paralysis occurs due to mishaps during fetal development.
The prevalence is estimated to be 1 in every 50,000 births and has equal incidence among males and females and can present with unilateral or bilateral facial paralysis. It is often diagnosed relatively early in the neonatal period due to impaired ability to feed due to incomplete closure of the lips. Milder cases may be diagnosed in early childhood or later due to delay in developmental milestones. There is also absence of mimicry, lack of smile and associated ocular motility dysfunction. Picciolini et al used observed that their 50 Italian pediatric patients population with MBS, the children exhibited global developmental delay at 1 year, motor, emotional and speech delays at 2 years, which trended toward normalization at 3 years of age with persistent weakness in hand-eye coordination and impaired facial expression. The children have normal intelligence, with 10% displaying cognitive impairment, and 30-4% may be diagnosed with autism.
MBS can be associated with other syndromes such as Poland Syndrome, Pierre Robin Sequence, Carey-Fineman-Ziter, and Klippel-Feil and can also manifest hand and feet anomalies as well.
What are the symptoms of Moebius Syndrome?
- Congenital facial paralysis with concomitant ocular abduction deficits.
- Other cranial neuropathies include: CN 5, 9, 10 and 12.
- Other abnormalities include: lingual hypoplasia, sensorineural hearing loss, craniofacial malformations (epicanthal folds and micrognathia), abnormalities of their extremities (syndactyly, pes planus, valgus femur), cardiac abnormalities
What causes Moebius Syndrome?
Alterations in cranial nerve nuclei limited to the brainstem and choroid plexus of the lateral ventricules.
Errors in the development of the vascular system have been implicated and genetic mutations in the following genes have also been attributed to the development of MBS through varied pathways: PLXND1, REV3L, MBS1, MBS2, MBS2 and HOX family genes (HOSA1, HOXB1, and SOX14.
How can Moebius Syndrome be treated?
Symptomatic Treatment: for example, inadequate sucking may necessitate nutritional supplementation in the neonatal period. Additionally, Botulinum toxin injections to the medial rectus muscle may help prevent contractures.
This condition requires multidisciplinary support and management. Due to the varied manifestations of this disorder, please check with your pediatrician, genetic counselor, otolaryngologist, ophthalmologist, facial plastic surgeon or plastic surgeon for further details.
References
- Picciolini Or, Porro M, Cattaneo E, Castelletti S, Masera G, Mosca F, Bedeschi MF. Moebius syndrome: clinical features, diagnosis, management and early intervention. Italian Journal of Pediatrics. 2016. 42:56-63.
- Kadakia S, Helman SN, Schwedhelm T, Saman M, Azizzadeh B. Examining the genetics of congenital facial paralysis – a closer look at Moebius syndrome. Oral Maxillofac zsurg. 2015. 19:109-116.
- McKay VH, Touil LL, Jenkins D, Fattah AY. Managing the child with a diagnosis of Moebius Syndrome: more than meets the eye. Arch Dis Child. 2016; 101:843-846.
Terzis JK, Anesti K. Developmental facial paralysis: a review. Journal of Plastic, Reconstructive & Aesthetic Surgery. 2011; 64:1318-1333.