Table of Contents

Möbius Syndrome

Möbius Syndrome

Described by Möbius as “Congenital Facial Diplegia” with bilateral abducens palsy in 1888
Diplegia= symmetrical bilateral palsy

Cause

Pathogenesis is unclear
Deletion/translocation in long arm of chromosome 13 in a few families
Timing of insult 4-6 weeks gestation when cranial nerve nuclei are rapidly developing
Trauma, illness or toxic exposure

Clinical Features

6th and 7th nerve palsies
- Usually bilateral but may be asymmetric
- Esotropia most common
- “Mask-like” facies
  - If incomplete palsy- upper division of facial nerve involved

Other Ocular features:

Small palpebral fissures
Epicanthal folds
Hypertelorism
Exposure or neurotrophic keratitis
Situs inversus of retinal vessels
Entropion
Ptosis
Head tilt
Amblyopia
Gaze palsy

Other Systemic Features

Extremities
- Syndactyly, polydactyly, brachydactyly, agenesis of digits, clubfoot
Swallowing and speech abnormalites from cranial V, IX and X palsies
Craniofacial abnormalities
- Micrognathia, Microstomia, Ear abnormalities, Bifid uvula, cleft palate
Dextrocardia
Defective musculature
- Missing pectoral and trapezius muscles
- Absence of sternal head of pectoralis major
Rib defects
Tongue hypoplasia
Mild Mental retardation

First signs:

Difficulty sucking, drooling, incomplete closure of eyelids
Lack of smiling response
Other cranial nerve abnormalities:
- V, IX,X and XII can be involved
Craniofacial abnormalities

Evaluation

Strabismus (Esotropia)
Amblyopia
Corneal health
Pediatric Genetics evaluation
- Craniofacial abnormalities in differential diagnosis
  - Nager syndrome (acrofacial dysostosis)
- Neuromuscular disease in differential diagnosis
  - Facioscapulohumeral (FSH) muscular dystrophy- shoulders primarily affected
  - Congenital or infantile myotonic dystrophy (slow relaxation of muscles after contraction)
    - Muscle wasting, cataracts, heart conduction defects, endocrine abnormalities
  - Charcot-Marie-Tooth disease
    - progressive loss of muscle and touch sensation in extremities
    - Usually in late childhood or early adulthood
    - Often first present with foot drop and claw toe

Strabismus Management

Abnormal Extraocular muscles
- Hypoplasia, aplasia and fibrous bands
Forced duction testing
Vertical Rectus transposition
Medial rectus botox (more effective if muscle not tight)
Medial rectus recession

strabismus, syndrome