Moebius syndrome is a rare disease, although its incidence seems to be increasing. The latest neurology and ophthalmology congresses in the world report an increase in the number of registered cases. We can say that the main feature of Moebius syndrome is the lack of ability to smile. Although individuals with this syndrome experience happy situations and would like to smile, they cannot do so. What is the treatment for Moebius syndrome?
Those who suffer from this rare disorder cannot do many of the classic and typical facial gestures. For example, the syndrome even affects the ability to move the eyes from side to side. Two pairs of cranial nerves, pair number six and pair number seven, are partially or completely undeveloped. These nerves manage the mimic muscles and the part of the muscles that performs some eye movements.
As we will see below, each pair of cranial nerves has specific functions. Nerve number six is what regulates the laterality of the eye. The number seven nerve is what we call the “facial nerve” because it manages facial expressions.
Moebius syndrome occurs in isolation. It is not uncommon for a family to have multiple confirmed cases. It is estimated that one in 120,000 people is born with this disease.
What are the cranial nerves?
To understand why Moebius syndrome has certain symptoms, we will first analyze the pairs of cranial nerves and their functions. The cranial nerves are:
- Optically: This is the nerve of sight.
- Trigemen: It is involved in chewing.
- Olfactory: Carries information to perceive odors.
- Hypoglossus: It innervates the muscles of the tongue and neck.
- Auditory: Transports heard information to the brain.
- Glossopharyngeal: Transmits some of the taste that the tongue captures.
- Pathetic: It innervates the muscles responsible for eye movements.
- External ocular motor: It is one of the nerves that Moebius syndrome affects the most.
- Wave: Extends outside the skull to reach the chest and abdomen.
- Accessory: It extends beyond the skull to the muscles of the neck and back.
- Oculomotor: This is the third cranial nerve and innervates part of the eye muscles.
Etiology of Moebius syndrome
It is important to clarify that, although it is known as syndrome, Moebius is what we know in genetics as a sequence. In sequences, there are several malformations at the same time, which come from a single anomaly.
In the case of the Moebius sequence, the abnormality is the lack of development or the total absence of nerve nuclei in the cranial nerves number six and seven. Both the imaging studies performed and the autopsies coincide with the diagnosis.
The etiology is not always genetic. There have been cases where the problem of cranial nerves has been caused by drugs. Misoprostol is the drug that has been most often associated with this problem, according to a group of researchers at the Universidad del Norte in Barranquilla, Colombia. This medicine is used for abortion. If it fails, the fetus may develop Moebius syndrome.
Symptoms of Moebius syndrome
- The ogival palace
- Lack of eyelids
- Hypersensitivity to the sun and strong lights
- Hearing problems due to fluid accumulation in the inner and middle ear
Treatment of Moebius syndrome: experiments
There is no cure for Moebius syndrome. Once installed, it is not completely reversible. Facial rehabilitation sessions have not been shown to be effective.
There is an experimental surgical treatment that has been initiated in Canada. It consists of an operation in which a muscle graft is performed in the area of the face to allow the expression of a smile.
It is estimated that the greatest success of the operation is when the patient is about 5 years old. Although the practice is promising, it is not available worldwide and the costs are prohibitive.
One of the struggles of the families of patients with Moebius syndrome is to avoid discrimination. For this reason, people try to sensitize the population, emphasizing that those affected have feelings, even if they cannot express them.
The treatment of Moebius syndrome continues to be analyzed by the medical world. Surgical projections are encouraging. It is essential to respect these patients and to understand that their inclusion in social life depends on a better knowledge of their condition.