Brainstem Differences


The base of the brain (brainstem) in some Spina Bifida children develops slightly differently than normal.  This is called the Arnold Chiari II malformation.

This is not usually a problem except your child may be unduly sensitive to noise and be prone to motion sickness.  A CT or MRI scan can be performed to locate the position of the brainstem. In rare cases, the brainstem will become trapped in the spinal column, coming under pressure as it grows. Where this happens, it is usually evident by six months of age (not before 3 months unless it is already a problem at birth) and does not develop after 12 months of age.

The brainstem holds the breathing centre, nerves that control swallowing and  that control the vocal cords and less importantly some of the nerves that control the tongue and some face movements.  About 1/3 of children with the Arnold Chiari II malformation will experience an increase in pressure on their brainstem which may show up in the following ways

  •     difficulty swallowing feeds-liquid and solids
  •     choking spells
  •     hoarse cry with noisy or croupy breathing-when the vocal cords don’t work properly.
  •     breath holding attacks
  •     very sensitive hearing (intolerance of high pitched noises especially)

It is important that parents observe their children for any of the above symptoms. Surgery to correct breathing or feeding problems will only be required by 1 in 30 children.

Children who exhibit either a harsh cry or croupy breathing are likely to undergo neurosurgery to relieve pressure on the vocal cords.  This involves the removal of part of the base of the skull and the back of the cervical spine to create more room.  A tracheotomy (breathing tube) is sometimes used to support the airway.

Children with the Arnold Chiari II malformation may experience problems with feeding and it can take some time for them to be able to swallow lumpy solids or textured foods.  It is important not to push these if your child gags on them.  It may be necessary to tube feed some children but in most cases, small amounts of thickened formula are given frequently along with smooth solids and anti-reflux medication (if required).  Crunchy foods that dissolve completely can be introduced over time. This allows children to chew without accidental lumps eg. crackers, rusks and biscuits.  It will be necessary to blend most food thoroughly.

An assessment of your child’s feeding can be done by a Speech Language Therapist or through the local feeding clinic.  This will usually be arranged by your Paediatrician if there are any concerns.