We have a baby with holoprosencephaly in the NICU. In holoprosencephaly, the forebrain of the embryo fails to develop properly. This leads to large amounts of fluid collection in the brain. the fluid collection becomes so large it compresses the brain matter and causes severe enlargement of the baby’s head. In the above image, the really white stuff on the outer edge is the skull. Just inside the skull in the gray is a thin line that represents the small amount of actual brain matter the baby has. All of the dark space in the center is the fluid collection. Everyone has fluid filled areas in the middle of each lobe of the cerebrum (Ventricles), but in these babies the ventricles are enormous).
This fluid can’t drain on its own so in some cases a neurosurgeon is called to place a ventricular-peritoneal shunt. A VP shunt is basically a long tube from the fluid filled space in the brain (Ventricle) to the lower abdomen (Peritoneum) that allows the otherwise trapped fluid to drain in to the abdomen where it is absorbed and removed from the body.
The baby in our unit has a moderate form of the deformity with few facial anomalies aside from the head enlargement. The most severe forms, which can include cyclopia (This link to the NIH page on cyclopia includes graphic images that you might not want to see), are usually fatal before birth. Some of the more severe forms can also be associated with cleft lip and palate (Again, this links to pictures, but not as bad as the cyclopia images).
Our baby is actually doing relatively well. The baby was placed a seizure medication shortly after birth and has had relatively few episodes since that time. Although most of these babies do not nipple well and need feeding tubes placed, this baby’s mother has gotten the baby to take small amounts of breast milk from a bottle. Neurosurgery has also put in a VP shunt and the head circumference is down form 60cm at birth down to 55cm in the 2 weeks since the shunt was placed. FYI: The average baby is 35cm at birth. My head circumference is roughly 60cm.
This is a best and worst scenario for a few reasons. It’s a worst patient because of the severity of the deformity and the poor prognosis, but it’s a best case as well. Being able to see a baby with this level of holoprosencephaly is quite rare, especially one that is doing relatively well. This mother spends all day with her baby and loves it with all her heart. She can’t wait to take the baby home.
Also, the baby is cute as hell.