Anatomy is essential in imaging cranyosynostosis,
and includes the major and minor sutures,
fontanels,
bones and major skull landmarks,
all of which have been depicted in figure 1.
The first step in assessing patients with an abnormal skull shape is a clinical examination in which almost all forms of monosutural craniosynostoses can be diagnosed.
Ultrasonography is the technique of choice for diagnosis of neonates and infants, showing preliminary diagnosis.
It is a less expensive,
nonradiating and easy-to-handle technique ensuring the diagnosis of craniosynostosis.
In many centers sonography is the standard investigation for infants with head deformities suspecting a suture pathology. However,
sonography is operator dependent,
requires special technologist training,
and is not feasible in infants older than 13 months.
( fig.9,
10,
11)
Plain skull radiography demonstrates moderate sensitivity and specificity in craniosynostosis including anteroposterior and lateral incidences.
Radiographs satisfies the clinical need in cases involving monosutural craniosynostosis, indicated in children with remaining diagnostic doubts after clinical and sonographic evaluation,
immediately prior to surgery or in non-surgical cases after the first year of life to access for additionally affected sutures.( fig.8,
10)
Syndromic cases are best evaluated directly with MDCT with 3D surface-rendered reconstructions,
positive cases having surgical consultation indicated. Numerous publications show its diagnostic performance,
with reported sensitivities of 96– 100%.
y.
Higher diagnostic performance is obtained when radiographs and CT are of good quality and interpreted by experienced reviewers.
This modality not only depicts the osseous pathology exquisitely,
but also allows for the detection of associated intracranial abnormalities,
including hydrocephalus and brain developmental anomalies,
asymmetric cranial morphology,
such as brain hemiatrophy and chronic subdural collections.( fig.10,
11,2,3,4,5)
The role of MRI in craniosynostosis has been limited due to its unreliability in identifying the cranial sutures.
However,
with advantages of radiation-free and excellent soft-tissue contrast,
MRI has been an important modality in combination with ultrasonography in infants with suspected associated intracranial anomalies and complications of craniosynostosis.
MRI is useful in the detection cortical and white matter abnormalities,
hydrocephalus and cerebral developmental defects,
such as myelination defects.
(fig.6,7)