Mobius Syndrome

Paul Julius Möbius. Source: Wikimedia Commons.

Mobius syndrome is a rare birth defect caused by the absence or underdevelopment of the 6th and 7th cranial nerves, which control eye movements and facial expression. People with this condition may have difficulty with facial expression (smiling, frowning, sucking, grimacing or blinking the eyes) and may be unable to move their eyes from side to side. The 3rd, 4th, 5th, 9th, 10th and 12th cranial nerves may also be affected. In addition, the syndrome may include skeletal involvement causing anomalies of the hands and feet. Respiratory problems, speech and swallowing difficulties, visual impairment, sensory integration dysfunction, sleep disorders, and decreased upper body strength may also be present.

Other Names

• Moebius syndrome
• Moebiüs sequence
• Congenital facial diplegia syndrome
• Congenital oculofacial paralysis

Illustration of the distribution of the cranial nerves. Source: Gray's Anatomy, 1918, Wikimedia Commons.

Signs and Symptoms

The first symptom, present at birth, is an inability to suck. Other symptoms can include:

• Lack of facial expression
• Feeding difficulties
• Swallowing difficulties, frequent choking
• The inability to squint or blink the eyes
• Absence of lateral eye movement
• Strabismus (crossed eyes)
• Drooling
• High palate
• Short or deformed tongue
• Limited movement of tongue
• Cleft palate
• Dental problems
• Hearing impairment
• Speech disorders
• Deformities of the hands and feet (such as clubfoot and missing or webbed fingers)
• Deformities of the tongue and jaw
• Motor difficulties

As children get older, lack of facial expression and the inability to smile become the dominant visible symptoms.

Approximately 30% of children with Mobius syndrome are reported to be on the autism spectrum. ^[1]

Causes

Mobius syndrome is thought to be genetic, and most cases are sporadic, occurring once in a family. There are some families, however, in which multiple people have Mobius Syndrome. The mode of inhertiance is not yet understood. Genetic counseling may be helpful for families with a history of Mobius Syndrome.

Diagnosis

Currently there is no diagnostic test for Mobius Syndrome. The diagnosis is made by clinical examination alone.

Treatment

There is no specific course of treatment for Mobius syndrome. Treatment is supportive and in accordance with symptoms. Infants may require feeding tubes or special bottles to maintain sufficient nutrition. Surgery may correct crossed eyes and improve limb and jaw deformities. Physical and speech therapy often improves motor skills and coordination, and leads to better control of speaking and eating abilities. Plastic reconstructive surgery may be beneficial in some individuals. Nerve and muscle transfers to the corners of the mouth have been performed to provide limited ability to smile.

Research

Recent discoveries

• The use of free tissue transfer for the treatment of facial paralysis in conditions such as Mobilus syndrome is discussed. ^[2]
• A recent study from Brasil defines the characteristic features of Mobius syndrome as the paralysis of the facial nerve and the horizontal gaze palsy. ^[3]
• The majority of patients with Mobilus syndrome were found to have hearing in the normal range in another recent study from Brazil. ^[4]

Current research

• An ongoing study is evaluating the use of photography and video intervention to improve self-esteem in patients with facial abnormalities in a number of syndromes, including Mobius syndrome. ^[5]

Expected Outcome

There is no cure for Mobius syndrome. In spite of the impairments that characterize the disorder, proper care and treatment give many individuals a normal life expectancy. The prognosis for otherwise normal development is excellent in most cases.

History

In the late 1880's a German physician, Paul Julius Moebius, MD, described the rare neurological condition of a man who had no facial expression, could not blink his eyes and could not move his eyes laterally. For over 100 years relatively little was known about this condition which affects primarily the 6th and 7th cranial nerves, but can affect any of the 12 cranial nerves. ^[6]

References

1. ↑ Moebius Syndrome Foundation web site. What is Moebius Syndrome?
2. ↑ Chuang DC. Free tissue transfer for the treatment of facial paralysis. Facial Plast Surg. 2008 May;24(2):194-203. Abstract
3. ↑ de Souza-Dias CR, Goldchmit M. Further considerations about the ophthalmic features of the Möbius sequence, with data of 28 cases. Arq Bras Oftamol. 2007 May-Jun;70(3):451-7. Abstract | Full Text
4. ↑ Griz S, Cabral M, Azevedo G, Ventura L. Audiologic results in patients with Moebiüs sequence. Int J Pediatr Otorhinolaryngol. 2007 Sep;71(9):1457-63. Epub 2007 Jul 20. Abstract
5. ↑ ClinicalTrials.gov. Positive Exposure: A Photography and Video Intervention for Individuals With Craniofacial Differences
6. ↑ Moebius Syndrome Foundation web site. About Us

External Links

Moebius Syndrome Foundation

Moebius1.org

Children's Craniofacial Association

March of Dimes Foundation

National Organization for Rare Disorders