Radiography
Findings
Plain radiographs are obtained easily and demonstrate osseous anatomy well. At a minimum, views should include anteroposterior (AP), Townes, and bilateral lateral films. Plain radiographs are useful for identifying the abnormalities of head shape (dolichocephaly, brachycephaly, and plagiocephaly) that are characteristic of the various forms of craniosynostosis.
Plain radiographs can be used for the following:
- Identifying prematurely fused sutures (Normal sutures are seen on plain images as serrated, nonlinear, lucent lines. Sutures in patients with craniosynostosis are usually straight with sclerotic heaped-up margins or are completely absent. The sclerotic margins may outline the sutures well and lead to the false impression that they are patent. Particular attention should be paid to the presence of this sclerotic margin and to focal sites of heaped-up margins, which are indicative of premature synostosis.)
- Demonstrating overall morphology of the cranium
- Identifying the presence of localized problems (constricting bony bands restricting growth)
- Identifying the presence of generalized problems (copper-beaten appearance, indicating elevated ICP)
- Identifying other skeletal anomalies
Degree of Confidence
Visualizing the length of all sutures is not always possible, and suture closure may be difficult to detect unless it is accompanied by an abnormal head shape.
False Positives/Negatives
Normal variations in the shape of the pediatric skull exist. For example, many formerly premature infants have long, narrow skulls resembling dolichocephaly but without sagittal synostosis. Many children also have asymmetric flattening of the occiput caused by habitually lying on 1 side of the head, without underlying suture abnormalities; this is called positional molding. These 2 types of skull deformities are more common than craniosynostosis.
Computed Tomography
Findings
CT scans provide a more detailed method for visualizing intracranial pathology and detailed anatomy of the calvaria and brain parenchyma. In contrast to plain radiographs, the skull base is visualized well, and hard and soft tissues of the craniofacial skeleton can be studied in detail.
- Neuroimaging is performed in children with isolated suture synostosis primarily to look for underlying brain damage or associated cerebral anomalies.
- Infants with trigonocephaly may have midline anomalies (eg, holoprosencephaly).
- Anomalies of the venous drainage and stenosis of the venous foramina at the skull base can occur with multisuture synostosis with both syndrome- and nonsyndrome-related causes.
- After abnormal or suggestive plain radiographic findings are noted, CT scans with bone windows with or without 3D reconstruction are frequently requested prior to surgical therapy.
- Features such as shallow anterior fossa, deformed dystopic orbits, abnormal calvarial contour, and asymmetric cranial base can be realistically depicted.
Degree of Confidence
The sensitivity of CT scans, when combined with physical examination and plain radiography, approaches 100%.
False Positives/Negatives
Even on CT scans, the entire length of every suture may not be clearly visible. Once again, normal variations in skull shape may pose a problem.
Magnetic Resonance Imaging
Findings
MRI shows better definition of intracranial soft-tissue structures than CT. In addition, MRI is useful in the detection of hydrocephalus and cerebral developmental defects, such as myelination defects and deformities of the maxilla resulting in airway compromise.
If children with craniosynostosis have abnormalities of tone or have diminished movements, MRI should be performed because it is the most sensitive method for detecting both cortical and white matter abnormalities.
False Positives/Negatives
MRI is not a strong modality for evaluating bony abnormalities and thus cannot be used as the primary method of evaluating craniosynostosis. MRI is used primarily for assessing associated brainstem and soft tissue abnormalities.
Ultrasonography
Findings
The recent literature has shown some advancement in the prenatal detection of craniosynostosis by using 3D versus 2D ultrasonography. A case was reported by Krakow et al in which prenatal 2D ultrasonographic findings were consistent with craniosynostosis.2 After 3D ultrasonography, positional molding was suspected instead. Neonatal radiographs confirmed that the case was that of positional molding.
With 3D ultrasonography, the full length of the suture is visible, which is not possible with conventional ultrasonography. Ultrasonography can also be useful in detecting bony abnormalities associated with the syndrome-related causes of craniosynostosis.
Degree of Confidence
Research is ongoing to determine the usefulness of ultrasonography as a tool in diagnosing craniosynostosis.
False Positives/Negatives
Ultrasonography is user dependent, and therefore, inexperienced personnel can miss the diagnosis of craniosynostosis.
More on Craniosynostosis |
| Overview: Craniosynostosis |
 Imaging: Craniosynostosis |
| Follow-up: Craniosynostosis |
| Multimedia: Craniosynostosis |
| References |
| « Previous Page | Next Page » |
References
Jabs EW. Toward understanding the pathogenesis of craniosynostosis through clinical and molecular correlates. Clin Genet. Feb 1998;53(2):79-86. [Medline].
Krakow D, Santulli T, Platt LD. Use of three-dimensional ultrasonography in differentiating craniosynostosis from severe fetal molding. J Ultrasound Med. Apr 2001;20(4):427-31. [Medline].
Behrman RE, Kuelman R, Jenson H. Craniosynostosis. In: Kliegman R. Nelson Textbook of Pediatrics. 16th. Philadelphia, Pa: WB Saunders Co; 2000:1831-2.
Cohen MM Jr. Craniosynostosis update 1987. Am J Med Genet Suppl. 1988;4:99-148. [Medline].
Goetz C, Pappert E. Textbook of Clinical Neurology. Philadelphia, Pa: Harcourt Brace & Co; 1999:533-4.
Kapp-Simon KA, Speltz ML, Cunningham ML, Patel PK, Tomita T. Neurodevelopment of children with single suture craniosynostosis: a review. Childs Nerv Syst. Mar 2007;23(3):269-81. [Medline].
Lin H, Ruiz-Correa S, Shapiro LG, Hing A, Cunningham ML, Speltz M. Symbolic shape descriptors for classifying craniosynostosis deformations from skull imaging. Conf Proc IEEE Eng Med Biol Soc. 2005;6:6325-31. [Medline].
Merkes J, Sarnat H. Child Neurology. 6th. Philadelphia, Pa: Lippincott Williams & Wilkins; 2000:351-4.
Mitsukawa N, Satoh K, Hayashi T, Furukawa Y, Suse T, Uemura T, et al. Sinus pericranii associated with craniosynostosis. J Craniofac Surg. Jan 2007;18(1):78-84. [Medline].
Rudolph A, Hoffman J, Rudolph C. Rudolph's Pediatrics. 20th. Stamford, Conn: Appleton & Lange; 1996:412-4.
Silverman FN, Caffey J, Kuhn JP. Mosby-Year Book. In: Essentials of Caffey's Pediatric X-Ray Diagnosis. Chicago, Ill: 1990:11-19.
Swaiman K, Ashwal S. Mosby-Year Book. In: Pediatric Neurology: Principles & Practice. 3rd. Philadelphia, Pa: 1999:276-84.
Further Reading
Keywords
premature fusion of cranial sutures, cranial sutures, simple craniosynostosis, compound craniosynostosis, cranial synostosis, synostosis, suture synostosis, sagittal synostosis, coronal synostosis, metopic synostosis, lambdoid synostosis, combined synostosis, scaphocephaly, dolichocephaly, brachycephaly, plagiocephaly, oxycephaly, trigonocephaly, kleeblattschädel deformity, Cloverleaf deformity, Crouzon disease, Chotzen syndrome, Apert syndrome
