Introduction

It is now well established that the growth of the brain is a major factor in shaping the craniofacial complex, particularly the cranial vault (Moss and Young, 1960). Numerous studies have also suggested that the cranial base (CB) plays a role in determining the shape of the craniofacial complex (Bjork, 1955; Enlow, 1976; Kerr and Adams, 1988). Intracranial pressure may also be implicated in the postnatal development of the CB. For example, the prolonged increased intracranial pressure in uncontrolled hydrocephalus (HC) results in well-defined cranial vault as well as CB changes (Kantomaa et al., 1987), which have been confirmed by experimentally induced HC in rats (Hoyte, 1991).

The most important factor in controlling HC is to maintain an adequate subdural pressure (Hakim and Hakim, 1984). A valve-regulated shunt device which insures unidirectional cerebrospinal fluid (CSF) circulation, has markedly improved prognosis for HC children (Fernell et al., 1988). However, this treatment modality is still prone to various complications such as shunt obstructions, mechanical failures, infections, and overdrainage of CSF (Serlo, 1985).

Earlier studies have shown definitive abnormalities in CB morphology. For example, a smaller sella turcica and the planum sphenoidale thickened and displaced superiorly (Kaufman et al., 1970). A cephalometric evaluation of five adults with untreated HC revealed that the CB was flat and anteriorly elongated (Kantomaa et al., 1987).