Congenital cranial dysinnervation disorders (CCDD):Primary/secondary muscle dysinnervation disorders arising from congenital developmental anomalies or complete absence of one or multiple cranial nerves
- Duane retraction anomaly
- Congenital fibrosis of extraocular muscles (CFEOM)
- Horizontal gaze palsy
- Congenital ptosis
- Congenital facial palsy
- Möbius’ sequence
Moebius syndrome is a congenital facial weakness combined with abnormal ocular abduction in most studies. In 1888, a German neurologist, Paul Julius Mobius, first described the clinical entity of Mobius syndrome. He reported patients with congenital and delayed facial and abducent nerve palsy. However, von Graaefe was the first to report patients with facial diplegias. Hallmarks of Mobius syndrome mainly consist of paresis of 6th and 7th nerves. It may or may not be associated with paralysis of other cranial nerves (III, V, VI, IX, X) and abnormalities of the limb (syndactyly, brachydactyly or absence of digits), chest wall, spine and soft tissues.
Aetiology of the syndrome still remains unknown, and most cases reported are sporadic.
- Maternal drug exposure: Misoprostol, thalidomide, cocaine, alcohol, benzodiazepines, ergotamine
Several features associated with Moebius syndrome are considered to derive from abnormal development of the rhombencephalon (hindbrain), which develops into the medulla, pons, and cerebellum. Although the pathogenesis remains unknown, an intrauterine vascular event linked to subclavian artery disruption or a toxic injury in the critical period during the first trimester has been proposed.
Broad spectrum of symptoms and signs in the cranio-maxillofacial region.
Complete/incomplete unilateral/bilateral facial paralysis associated with bilateral abducens nerve palsy:Non-progressive, congenital, unilateral or bilateral palsy of the 6th and 7th cranial nerves
- Incomplete closure of eyelid during sleep
- Drooling of saliva from the mouth
- Difficulty in sucking
- Masklike facies: Lack of facial movement when crying, inability to smile
- Asymmetry of angles of mouth
- Indistinct speech secondary to the inability to close the lips, leading to labial sound
- Primary motor problems: Hypotonia, musculo-skeletal dysmorphism, delay in righting, locomotion and clumsiness.
- Limb abnormalities: Lower extremity truncating defects, oligodactyly, syndactyly, and/or talipes equinovarus
- Klippel Feil syndrome (KFS): Abnormal fusion of ≥ 2 cervical vertebrae
- Poland anomaly: Ipsilateral aplasia/hypoplasia of the pectoralis muscle plus hand and digit anomalies
- Feeding disorders: Sucking-swallowing difficulty, breathing problems, lack of the sensitivity of the orofacial area, dysphagia with the need, in severe cases, for a gastrostomy
- Facial malformations: Depressed nasal bridge, anteverted nostrils, thin upper lip, downturned mouth corners, bilateral epicanthus, and micrognathia
- Language difficulties: Dyslalia, mechanical disorders of phonological coding and speech structure and writing were common.
- Visual impairment: Scanning, exploration and visual-perceptual deficits, and, in some cases, corneal ulcers.
- Cognitive retardation
International Classification of functioning Children and Youth (ICF-CY) framework:GOLD STANDARD framework for interpreting functions (vs impairment), activities (vs disability) and participation (vs handicap), in children with MBS and for evaluation and intervention of the familial and social environment
Radiography:In accordance with affected regions
- Agenesis of corpus callosum, absent septum pellucidum, hypoplastic olfactory nerves, mild brainstem hypoplasia, and simplified gyral patterns
- Hypoplastic vertebral arteries
- Melkersson-Rosenthal syndrome
- Congenital facial muscular atrophy
- Muscular dystrophy
- Cerebral palsy
- Congenital myopathies
Definitive medical treatment is not available for Mobius syndrome, therefore, medical care is only supportive and symptomatic. Parental education plays a major role in the patient’s life.
Surgical management:Restoration of motion secondary to the facial nerve palsy that results in mask-like facies and inability to smile is the prime aim of the treatment plan.
- Plastic surgery reconstruction with muscle transplantation (ideally at an early age)
- Ocular surgeries
- Orthognathic surgeries
- Surgical corrections for other associated abnormalities
Other intervention programs:
- Physical therapy (for congenital orthopedic problems)
- Occupational therapy (help with daily activities)
- Speech therapy (for severe facial nerve paralysis)