Sinus Hypoplasia and Intracranial Hypertension in Pycnodysostosis (SHIHP): A New Disease Process? -

Pycnodysostosis is a rare autosomal recessive skeletal dysplasia caused by absence of active cathepsin K. Intracranial hypertension represents a rarely reported, life threatening complication of pycnodysostosis. We describe, for the first time, two children with pycnodysostosis who presented with raised intracranial pressure and were found to have intracranial venous sinus hypoplasia. The combination of Sinus Hypoplasia and Intracranial Hypertension in Pycnodysostosis (SHIHP) has not been previously reported. In a patient with pycnodysostosis, neurological and ophthalmological assessment is necessary and MR Brain including venography should be considered. The management of such a patient is challenging in particular due to the uncertainty as to the mechanism of the raised intracranial pressure in the face of small ventricles and an open fontanelle. Multi-disciplinary team management including the geneticist, ophthalmologist, neurologist, neurosurgeon, and the metabolic bone team is required. Surgical options include CSF diversion and cranial vault remodelling. The interplay of venous sinus hypoplasia, intracranial vault abnormalities, and raised intracranial pressure in a patient with pycnodysostosis shall be presented and discussed.