The Chiari malformation may be asymptomatic or present with ataxia, spasticity or abnormalities in breathing, swallowing or sleeping.Due to the impaired venous outflow, which may be further complicated with an Arnold–Chiari malformation, there is often a clinical image of hydrocephalus present. Hydrocephalus is seen in 6.5 to 8% of patients with Aperts syndrome, 25.6% in patients with Crouzons syndrome and 27.8% of those with Pfeifers syndrome.Ventriculomegaly is a usual finding in children with the Apert syndrome. Neurobehavioural impairment
Neurobehavioural impairment includes problems with attention and planning, processing speed, visual spatial skills, language, reading and spelling. A decreased IQ may also be part of the problems.It has been suggested that these problems are caused by a primary malformation of the brain, rather than being a consequence of the growth restriction of the skull and elevated intracranial pressure. Some evidence for this statement has been provided by studies using computed tomographic (CT) scans and magnetic resonance imaging (MRI) to identify differences between the structures of the brains of healthy children and those affected with craniosynostosis. It has been found that corrective surgery of the cranial vault alters the morphology of the brain compared with the situation before surgical intervention. However the structure was still abnormal in comparison to children without craniosynostosis. Causes
Advances in the fields of molecular biology and genetics, as well as the use of animal models have been of great importance in expanding our knowledge of suture fusion.
Physical examination
Fundoscopy should always be performed in children with craniosynostosis. It is used to find papilledema which is sometimes the only symptom of elevated intracranial pressure shown in these children.Other parts of the physical examination include the measurement of the head circumference, the assessment of the skull deformity and the search for deformities affecting other parts of the body. The head circumference and the growth curve of the head provide important clues into making a differentiation between craniosynostosis, primary microcephaly and hydrocephalus. This differentiation has an important influence on the further treatment of the child.In a recent article Cunningham et al. described several steps in which a pediatrician should observe the patient to assess skull deformity:

The first is looking with a birds eye view at the patient while the patient preferably faces the parent while sitting on the parents lap. The goal is to assess the shape of the forehead, the skull length, the width of the skull, position of the ears and the symmetry of the frontal bones and [occiput]. The second is looking at the patient from behind while preferably the child is in the same position as described above. It is important to look at the skull base (to determine whether it is level or not), the position of the ears and to the mastoid (to spot the possible presence of a bulge). The third point of view is the frontal view.