An increase in growth at the metopic and the sagittal suture accounts for the parallel plane and will result in bulging at the temporal fossa. Compensatory growth in the perpendicular plane occurs on the side of the head with the patent coronal suture, the contralateral side. Half of the forehead will bulge forwards. Assessment of the skull from a top view shows asymmetry of the frontal bones, an increased width of the skull and a forward displacement of the ear at the ipsilateral side of the head. Assessment of the skull from a frontal view will show asymmetrical features of the face, including a displacement of the chin point of the jaw and a deviation of the tip of the nose. The chin point is located more to the contralateral side of the head, due to the ipsilateral forward displacement of the temporomandibular joint together with the ear. The tip of the nose will also point towards the contralateral side. Complications based on the skull deformation include malocclusion of the jaw, in as many as 90%; a subtle form of strabismus, caused by the asymmetrical placement of the orbits; and refractive error, particularly astigmatism, due to asymmetrical development of the orbits. Posterior plagiocephaly
Unilateral lambdoid synostosis is also called posterior plagiocephaly, indicating that this gives, just like unilateral coronal synostosis, a skew head.
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.