The presence of dural tear is necessary for this to occur. This does not happen with an intact dura, as it expands with the growing brain .The skull enlarge in response to the growing brain. There are other associated pathological changes that occur with an enlarging skull fracture, these are cystic degeneration of the underlying parenchyma, enlargement of the ipsilateral ventricle towards the skull defect. Occasionally there is also CSF collection under the skull defect. The patient presents with a pulsatile swelling, headaches, and occasionally contra-lateral neurological deficits.
Seizures can also occur.
The proper management is to deal with the basic pathology i.e the dural tear and the skull defect. The dural edges need to be exposed and this would need removal of bone. The dural edges are then dissected from the underlying parenchyma and repaired in a water tight manner by using some form of dural graft. Following that the skull defect is repaired by cranioplasty, using autologous bone or metal if the skull defect is too large to be covered with bone. This is a curious condition that occurs in infants and usually the result of trauma.