Pierre Robin Sequence

I realize that in the past few weeks I have mentioned numerous times that Ben has Pierre Robin (pronounced “Roban”) Sequence but I have never actually explained what it is and exactly what we are dealing with.




Simply put Pierre Robin is not a syndrome or a disease. However that is were it stops being simple as it can be part of another disease or syndrome.

It is usually referred to as Pierre Robin Sequence, although it is also know as "Pierre Robin Malformation Sequence", "Robin Sequence", "Robin Anomalad", and "Cleft Palate, Micrognathia and Glossoptosis."

It is a birth condition that involves the lower jaw being either small in size (micrognathia) or set back from the upper jaw (retrognathia). As a result, the tongue tends to be displaced back towards the throat, where it can fall back and obstruct the airway (glossoptosis). Most infants, but not all, will also have a cleft palate. Ben does indeed have the cleft palate.

The basic cause appears to be the failure of the lower jaw to develop normally before birth. During the early weeks in pregnancy, the lower jaw grows rapidly, allowing the tongue to descend from between the two halves of the palate. If, for some reason, the lower jaw does not grow properly, the tongue can prevent the palate from closing, resulting in a cleft palate. The small or displaced lower jaw also causes the tongue to be positioned at the back of the mouth, possibly causing breathing difficulty at birth. This “sequencing” of events is the reason why the condition has been classified as a deformation sequence. For some, these physical characteristics may result from another syndrome or chromosomal condition. Luckily it looks like Ben's case is isolated.

Robin Sequence/Complex is rather uncommon. Frequency estimates range from 1 in 20,000 to 50,000 births, based on how strictly the condition is defined.

It is important to understand that Robin Sequence/Complex can occur by itself (described as “isolated”) or as a feature of another syndrome. Parents who have had one child with isolated Robin Sequence probably have between a 1 and 5% chance of having another child with this condition.

When Robin Sequence/Complex is observed in patients with Stickler Syndrome, Velocardiofacial Syndrome, or Treacher Collins Syndrome, genetic/chromosomal factors will influence whether more affected children will be born. Robin Sequence/Complex also occurs in children with environmentally-induced (“teratogenic”) syndromes such as Fetal Alcohol Syndrome and Fetal Hydantoin Syndrome.This is why we had to have genetic testing done at the IWK, although at the moment it doesn't seem likely that there is even a possibility of an associated syndrome.

Robin Sequence/Complex, like most birth defects, varies in severity from child to child. Some children may have more problems than others. Problems in breathing and feeding in early infancy are the most common. Parents need to know how to position the infant in order to minimize problems (i.e., not placing the infant on his or her back). For severely affected children, positioning alone may not be sufficient, and the pediatrician may recommend specially-designed devices to protect the airway and facilitate feeding. Some children who have severe breathing problems may require a surgical procedure to make satisfactory breathing possible.
The pediatrician or ear, nose, and throat specialist will also carefully monitor the baby for ear disease. Virtually all children with cleft palate are prone to build-up of fluid behind the eardrum. The placement of ventilation tubes in the eardrums may be recommended to reduce fluid build-up. Since ear infections can cause temporary hearing loss that can affect speech and language development, the infant’s hearing should also be monitored from early infancy by an audiologist.

In many patients, the lower jaw (mandible) grows rapidly during the first years of life. In some children, the jaw may grow so quickly that by the time the child is approximately four to six years of age, the profile looks normal. Children who do not experience this “catch-up” growth may require surgery on their jaws.

The cleft palate, needs to be surgically closed. The timing of the surgery depends on the child’s individual growth and development, but it is generally done at 1 to 2 years of age. Because children with cleft palate are at higher risk for delayed or defective speech development, they should be monitored by a speech pathologist throughout early childhood.

I obviously haven't gone into any great depth, especially with some of the syndromes that can be seen with PRS. Ben has been tested and will continued to be followed to make sure that this is in fact isolated PRS.

No wonder I am a nervous wreck!