Question
The infant has had severe regurgitation since birth. Recently, it was noticed that the fontanelle has a slight concavity, although not large, it can be felt to be protruding, and there is no visible pulsation. The baby shaved the lanugo at 40 days old and has not grown hair since. The baby can follow objects with their eyes, smile and laugh, and can roll over, but the regurgitation persists.
Answer
A common cause of a slightly concave fontanelle is increased intracranial pressure. If the baby has had conditions such as hypoxia or asphyxia, it could lead to cerebral edema, causing the fontanelle to protrude. Cerebrospinal fluid accumulation is also a possible cause. These conditions need to be confirmed through brain MRI.