External cranial expansion as treatment of intracranial hypertension. Technical note.

Intracranial hypertension may be idiopathic or due to multiple etiologies. Some bone dysplasias and chronic shunt overdrainage syndrome may sometimes lead to intracranial hypertension associated with craniocerebral disproportion due to thickening of cranial diploe. The internal cranial expansion procedure has been used for patients with intracranial hypertension, whether or not associated with craniocerebral disproportion. Its purpose is to increase the intracranial volume by drilling down the inner table. This technique enables the craniocerebral disproportion to be improved and intracranial hypertension reduced. In other etiologies of intracranial hypertension with non-thickened diploe, internal cranial expansion may not be enough to resolve the hypertension. For these cases we propose a modification of the technique by expanding the cranial vault outwards; external cranial expansion. We describe this technique as used in a pediatric patient who presented with chronic headache, tonsillar ectopia, and sleep apnea syndrome. This patient also had a multisuture craniosynostosis, a non-thickened diploe, and intracranial hypertension.