Hydrocephalus and Craniosynostosis

The occurrence of hydrocephalus in the background of craniosynostosis is very rare in patients with single suture affection (0.2–1.8%) but is a relevant factor of treatment in multiple suture synostosis or syndromic diseases (15–60%). Pathophysiological factors contributing to CSF circulation disturbances in craniosynostosis patients are heterogeneous but two main factors need to be taken into account such as venous outflow restriction and obstruction of major CSF pathway mainly due to possible compression of posterior fossa central nervous structures anatomy. Primary goal of treatment in craniosynostosis in these cases is the effective and sustainable restoration of intracranial volume to enable regular brain structure development and liberate the venous outflow as well as CSF circulation. Among those techniques, posterior vault expansion and cranio-cervical decompression appear to be most relevant. Although secondary interventions directed towards hydrocephalus treatment, especially CSF diverting shunt implantation, should be tried to avoid in this strategy. Despite consequent treatment, however, in rare cases this may still be necessary. In those, endoscopic treatment by e.g. ventriculocisternostomy in patients with major CSF pathway obstruction may be considered as first option. If a shunt implantation appears to be mandatory, overdraiange must be inhibited at all costs in order avoid negative ICP induced calvarial growth restriction or secondary correction loss. Patients must undergo rigorous follow up especially until adolescence in order to detect shunt related sequelae affecting calvarial growth potentials.