Mobius syndrome is a very rare congenital disorder characterized by palsies of various cranial nerves, most commonly of the facial and abducens nerves. Main symptoms, developing as early as infancy and during the neonatal period, are incomplete lip closure, poor facial expression, and a fixed eye gaze, together with facial and limb abnormalities. The diagnosis primarily rests on clinical criteria, as the exact etiology of Mobius syndrome remains unknown. Familial cases have been described.
Mobius syndrome (MS) is considered to be a rare disorder in clinical practice, with estimated incidence rates of 1 in 250,000 births . The exact cause of this syndrome, as well as its pathogenesis, remain unknown, with current hypotheses involving genetic mutations and pathological events during embryogenesis    . Although familial cases exist, most cases develop Mobius syndrome sporadically and the clinical presentation may be visible from neonatal period  . The most important features of MS are palsies of the facial (VII) and abducens (VI) cranial nerves  . Reduced facial mimicry (expression during smiling and crying are particularly affected) appearing either in a unilateral or bilateral fashion, and feeding difficulties due to incomplete lip closure that impairs sucking are main signs of facial nerve palsy  . Conversely, abducens nerve palsy is associated with a range of ocular abnormalities, as palsies of other cranial nerves responsible for innervating the ocular muscles (the oculomotor and the trochlear, or III and IV, respectively)  . Commonly reported findings are a fixed gaze, strabismus (either convergent or divergent), defects in abduction/adduction, and ptosis   . Additionally, hypoplasia of the tongue (hypoglossal nerve palsy), speech difficulties, and impaired swallowing (stemming from trigeminal, glossopharyngeal and/or vagus nerve palsies) are also reported in many patients  . Furthermore, cranial nerve palsies are accompanied by anatomical changes of the face (micrognathia, microphthalmia, smaller ears, a bifid uvula) and the musculoskeletal system (torticollis, syndactyly, brachydactyly, clubfoot, and muscular agenesis, particularly of the chest wall)    . Finally, studies identified autism and mental retardation in up to a third of cases .
- Failure to Thrive
Additionally, the patient demonstrated failure to thrive during infancy and childhood, many dysmorphic features, lower limb anomalies, and hypogonadism in adulthood, but his intelligence was in the normal range. [ncbi.nlm.nih.gov]
Treatment of pulmonary disease must be complemented by measures such as food texture modification, dietetic review, parental counselling, and re-education aimed at preventing failure to thrive. [neurologia.com]
On neurological examination, absent blink reflex, jaw ankylosis, absent gag reflex, and tongue atrophy were frequently observed. Poland anomaly and clubfoot were present in three and six patients, respectively. [ncbi.nlm.nih.gov]
- Hearing Impairment
impairment Deafness Hearing defect [ more ] 0000365 High palate Elevated palate Increased palatal height [ more ] 0000218 Hypogonadotrophic hypogonadism 0000044 Microdontia Decreased width of tooth 0000691 Micrognathia Small lower jaw Small jaw Little [rarediseases.info.nih.gov]
It makes me smile ear to ear every time I hear it. "Our journey would be so much harder if he didn't have such a hearty, wonderful laugh." 'WHY WOULD SOMEONE DO THIS TO ME?' [thesun.co.uk]
Brain stem necrosis resulting from a vascular deficiency has been offered as a possible pathogenetic explanation.(2) The strabismus in Möbius syndrome is congenital esotropia with bilateral limitation in abduction. [ncbi.nlm.nih.gov]
Clinical History A 14-year-old female presented permanent convergent strabismus and absence of facial mimic in the neurological evaluation. [eurorad.org]
Strabismus surgery in children with Mobius syndrome. J AAPOS. 2000;4:58–59. doi:10.1016/S1091-8531(00)90014-4 [CrossRef] Sun LL, Gole GA. Augmented vertical rectus transposition for the treatment of strabismus in Mobius syndrome. [healio.com]
Taylor, Strabismus/ Fibrosis syndromes, 47 Pan-Hellenic Congress of ophthalmology, Thessaloniki, Northern Greece Society of Ophthalmology, 2014 [eyewiki.aao.org]
- Hand Deformity
Claw hand Claw hand deformities Claw hands Claw-hand deformities Split-hand [ more ] 0001171 Sporadic No previous family history 0003745 Syndactyly Webbed fingers or toes 0001159 [rarediseases.info.nih.gov]
Club foot deformities will need to be corrected by an orthopedic surgeon. Hand deformities are most often characterized by an underdeveloped hand (or, symbrachydactyly). [drpanossian.com]
One common association is the Möbius-Poland anomaly, in which the facial and gaze abnormalities are accompanied by absence of one pectoral muscle with or without ipsilateral hand deformity (12, 13). [neuroophthalmology.ca]
Musculoskeletal involvement included thoracic anomalies observed in 5 %, absence or hypoplasia of pectoralis major muscle in 3 %, chest, arms and hand deformities in 14 %, clubfeet in 32 %, and scoliosis in 6 %. [ijponline.biomedcentral.com]
Face, Head & Neck
- Mask-like Facies
A 4-year-old boy presented with mask-like facies noted at birth after a 34-week pregnancy. Examination revealed bilateral facial and abducens nerve paralysis with no other neurological abnormalities. [ncbi.nlm.nih.gov]
The main nerves affected are the sixth (CN VI) and the seventh (CN VII) which results in abnormal gazing and mask like facies. [eyewiki.aao.org]
The treatment of patients with Möbius syndrome is directed toward the restoration of motion secondary to the facial nerve palsy, which results in mask-like facies and inability to smile. [ajnr.org]
80%-99% of people have these symptoms Abnormality of the voice Voice abnormality 0001608 Facial palsy Bell's palsy 0010628 Feeding difficulties in infancy 0008872 Mask-like facies Expressionless face Lack of facial expression Mask-like facial appearance [rarediseases.info.nih.gov]
- Short Neck
neck Decreased length of neck 0000470 Short phalanx of finger Short finger bones 0009803 Split hand Claw hand Claw hand deformities Claw hands Claw-hand deformities Split-hand [ more ] 0001171 Sporadic No previous family history 0003745 Syndactyly Webbed [rarediseases.info.nih.gov]
Additional features were shortness of the neck associated with torticollis. [doi.org]
- Cranial Nerve Involvement
Lower cranial nerve involvement, leading to respiratory, swallowing, and cardiac difficulties, was also present. Pathologic examination of the brainstem showed absent or hypoplastic third, seventh, tenth, and twelfth nerve nuclei. [ncbi.nlm.nih.gov]
In addition to the 2 above strict clinical criteria, additional signs or symptoms may also be present, including, but not limited to: – Other cranial nerve involvement – Strabismus (misalignment of the eyes) – Hearing loss – Club foot – Limb reduction [moebiussyndrome.org]
The most common cranial nerve involved is the 6th cranial nerve (abducent). The oculomotor and trochlear can also be involved. [annsaudimed.net]
Results Involvement of the VII cranial nerve (total/partial, bilateral or unilateral) was present in 96 % of patients, and of the VI nerve in 85 %. [ijponline.biomedcentral.com]
- Abnormal Gait
[…] disturbance Abnormal gait Abnormal walk Impaired gait [ more ] 0001288 Hypoplasia of the brainstem Small brainstem Underdeveloped brainstem [ more ] 0002365 Infantile muscular hypotonia Decreased muscle tone in infant 0008947 Intellectual disability, [rarediseases.info.nih.gov]
[…] recognition of objects and shapes, but the ocular movements provide the functions of the "where", that is, the location of objects, providing data on spatial orientation, the perception of movement and the third dimension (across saccades, optokinetic nystagmus [ijponline.biomedcentral.com]
Because of the rare occurrence of Mobius syndrome, the diagnosis may be difficult to make, especially in cases with milder phenotypes. For this reason, a detailed history that will assess the main symptoms, as well as their onset and severity (the parents are often the most reliable source, as young children are the main patient population) must be obtained. The physical examination, however, which allows the physician to identify signs of cranial nerve palsies and facial/musculoskeletal abnormalities, is the critical part of the diagnostic workup. A complete inspection of the body and a comprehensive neurological workup are key components. MS remains a diagnosis on clinical grounds, but imaging studies of the brain, such as magnetic resonance imaging (MRI), can provide additional clues by detecting hypoplasia of cranial nerves, their nuclei and their branches  . Calcifications of the brainstem have also been reported on computed tomography (CT) by isolated studies . Despite the fact that certain genetic mutations have been revealed in patients with MS   , specific genetic tests are yet to be designed.
From the WEST scientific·clinical From the EAST traditional·alternative There is no specific course of treatment for Moebius syndrome. Treatment is supportive and in accordance with symptoms. [goldbamboo.com]
This surgical treatment resulted in marked improvement of said deficits. [J Pediatr Ophthalmol Strabismus. 2017;54:e81-e82.]. [ncbi.nlm.nih.gov]
Read More Read Less Treatment Treatment There is no specific course of treatment for Moebius syndrome. Treatment is supportive and in accordance with symptoms. Infants may require feeding tubes or special bottles to maintain sufficient nutrition. [ninds.nih.gov]
Read PDF Candidates for Moebius Syndrome Treatment Moebius syndrome treatment is usually performed on children before they enter school. [facialparalysisinstitute.com]
Patient: Moebius Syndrome Factsheet with description, pathogenesis, associated abnormalities, recognition, management and prognosis. [curlie.org]
Read More Read Less Prognosis Prognosis There is no cure for Moebius syndrome. In spite of the impairments that characterize the disorder, proper care and treatment give many individuals a normal life expectancy. Clinical Trials Clinical Trials [ninds.nih.gov]
What is the prognosis? With close medical attention, the prognosis for most children with this condition is positive. Reviewed by: Saoussen Salhi, MD This page was last updated on: 4/23/2018 8:47:38 AM [nicklauschildrens.org]
[…] ventriculomegaly without obstructive hydrocephalus, especially frontal horn prominence corpus callosum dysplasia hippocampal malrotation cerebellar hypoplasia, especially vermian hypoplasia cerebral aqueduct stenosis with hydrocephalus Treatment and prognosis [radiopaedia.org]
Prognosis Children may crawl and walk later. Most children with Moebius Syndrome eventually catch up. Speech problems often respond to therapy, but may persist due to impaired mobility of the tongue and/or mouth. [patient.info]
Although in many cases, evidence of an intrauterine vascular insult may be identified, a contributing genetic etiology should be considered, even in cases with strictly unilateral features. [ncbi.nlm.nih.gov]
Etiology is multifactorial, and several theories have been proposed, with the most supported theory being of a transient ischemic or hypoxic insult to the fetus. Infectious and genetic etiologies have also been proposed. [radiopaedia.org]
Epidemiology In 2007, the Moebius Syndrome Foundation estimated that there were at the time a total of approximately 2,000 cases of Moebius Syndrome worldwide . [physio-pedia.com]
Smith, Epidemiology of autism: Prevalence, associated characteristics, and implications for research and service delivery, Mental Retardation and Developmental Disabilities Research Reviews, 4, 2, (97-103), (1998). [doi.org]
Epidemiology [ edit ] It is estimated that there are, on average, 2 to 20 cases of Möbius syndrome per million births.   Although its rarity often leads to late diagnosis, infants with this disorder can be identified at birth by a "mask-like" [en.wikipedia.org]
Epidemiology Mobius syndrome is a rare disorder. Only approximately 300 cases have been described in the English-language literature. [emedicine.medscape.com]
The pathophysiology of Möbius syndrome has been debated for decades. A vascular etiology is currently favored because it explains the wide clinical spectrum of this syndrome. [ncbi.nlm.nih.gov]
Pathophysiology: The complete pathophysiological description of Möbius syndrome remains elusive. Whether nerve, brainstem, or muscle aplasia is the primary event has not been established. [baillement.com]
A great deal of useful information, as well as support group information, is available on the Web site.  Pathophysiology Numerous theories exist concerning the primary underlying pathogenesis of Möbius syndrome. [emedicine.medscape.com]
Primary prevention Since it's a genetic disorder, not much can be done about prevention, but early screening of all neonates is required. [eyewiki.aao.org]
Prevention Moebius syndrome cannot be prevented as it is genetic. Treatment requires special care and monitoring by specialists. How is it diagnosed? At Medanta, the diagnosis is made on the basis of symptoms described by the patient. [medanta.org]
CONCLUSION(S): The early use of orthopedic appliances was important to prevent malocclusion and glossoptosis. Attempted abortion with misoprostol is associated with an increased risk of MS in infants. [ncbi.nlm.nih.gov]
Furthermore, the possibility to investigate a larger number of cases expands the opportunity to better characterize clinical conditions, methods of assessment, prognosis, and prevention program development, as well as health promotion of individuals diagnosed [arquivosdeorl.org.br]
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